diff --git a/core/src/main/java/art/arcane/iris/generation/bake/BakeCache.java b/core/src/main/java/art/arcane/iris/generation/bake/BakeCache.java
new file mode 100644
index 000000000..5054c537c
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/bake/BakeCache.java
@@ -0,0 +1,7 @@
+package art.arcane.iris.generation.bake;
+
+public interface BakeCache {
+    ColumnBake get(int chunkX, int chunkZ);
+
+    ColumnBake getIfPresent(int chunkX, int chunkZ);
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/bake/BakePlane.java b/core/src/main/java/art/arcane/iris/generation/bake/BakePlane.java
new file mode 100644
index 000000000..a915f3222
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/bake/BakePlane.java
@@ -0,0 +1,26 @@
+package art.arcane.iris.generation.bake;
+
+public enum BakePlane {
+    REGION(false),
+    BASE_BIOME(false),
+    BASE_HEIGHT(true),
+    NATURAL_HEIGHT(true),
+    NATURAL_TRUE_BIOME(false),
+    HEIGHT(true),
+    TRUE_BIOME(false),
+    ROCK(false),
+    FLUID(false),
+    CAVE_BIOME(false);
+
+    static final BakePlane[] PLANES = values();
+
+    private final boolean doubles;
+
+    BakePlane(boolean doubles) {
+        this.doubles = doubles;
+    }
+
+    public boolean doubles() {
+        return doubles;
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/bake/BakeRegistry.java b/core/src/main/java/art/arcane/iris/generation/bake/BakeRegistry.java
new file mode 100644
index 000000000..205982885
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/bake/BakeRegistry.java
@@ -0,0 +1,41 @@
+package art.arcane.iris.generation.bake;
+
+import java.util.Arrays;
+import java.util.IdentityHashMap;
+import java.util.Objects;
+
+public final class BakeRegistry<T> {
+    private final Object lock = new Object();
+    private volatile IdentityHashMap<T, Integer> ids = new IdentityHashMap<>();
+    private volatile Object[] values = new Object[16];
+    private int size;
+
+    public short id(T value) {
+        Objects.requireNonNull(value, "Registered value");
+        Integer known = ids.get(value);
+        if (known != null) {
+            return known.shortValue();
+        }
+        synchronized (lock) {
+            Integer existing = ids.get(value);
+            if (existing != null) {
+                return existing.shortValue();
+            }
+            if (size == Short.MAX_VALUE) {
+                throw new IllegalStateException("Bake registry is full");
+            }
+            Object[] grown = size == values.length ? Arrays.copyOf(values, size * 2) : values;
+            grown[size] = value;
+            values = grown;
+            IdentityHashMap<T, Integer> next = new IdentityHashMap<>(ids);
+            next.put(value, size);
+            ids = next;
+            return (short) size++;
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    public T value(int id) {
+        return (T) values[id];
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/bake/ChunkBakeCache.java b/core/src/main/java/art/arcane/iris/generation/bake/ChunkBakeCache.java
new file mode 100644
index 000000000..b1466b5a7
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/bake/ChunkBakeCache.java
@@ -0,0 +1,153 @@
+package art.arcane.iris.generation.bake;
+
+import art.arcane.iris.generation.cache.ConcurrentClockCache;
+import art.arcane.iris.generation.stream.ProvisionalSampling;
+
+import java.util.Objects;
+
+public final class ChunkBakeCache implements BakeCache {
+    private static final ThreadLocal<int[]> SPARSE = ThreadLocal.withInitial(() -> new int[1]);
+
+    private final PlaneSource source;
+    private final ThreadLocal<Recent> recent = ThreadLocal.withInitial(Recent::new);
+    private volatile ConcurrentClockCache<ChunkPlanes> entries;
+
+    public ChunkBakeCache(PlaneSource source, int capacityChunks) {
+        this.source = Objects.requireNonNull(source, "Bake plane source");
+        this.entries = new ConcurrentClockCache<>(Math.max(16, capacityChunks));
+    }
+
+    @Override
+    public ColumnBake get(int chunkX, int chunkZ) {
+        return planes(chunkX, chunkZ).columnBake(source);
+    }
+
+    @Override
+    public ColumnBake getIfPresent(int chunkX, int chunkZ) {
+        ChunkPlanes planes = planesIfPresent(chunkX, chunkZ);
+        return planes == null ? null : planes.columnBake();
+    }
+
+    public int capacity() {
+        return entries.capacity();
+    }
+
+    public synchronized void ensureCapacity(int chunks) {
+        ConcurrentClockCache<ChunkPlanes> current = entries;
+        if (current.capacity() >= chunks) {
+            return;
+        }
+        ConcurrentClockCache<ChunkPlanes> resized = new ConcurrentClockCache<>(chunks);
+        current.forEach(planes -> resized.putIfAbsent(key(planes.chunkX(), planes.chunkZ()), planes));
+        entries = resized;
+    }
+
+    public void clear() {
+        ConcurrentClockCache<ChunkPlanes> current = entries;
+        entries = new ConcurrentClockCache<>(current.capacity());
+        current.clear();
+    }
+
+    public long[] census() {
+        long[] counts = new long[BakePlane.PLANES.length + 1];
+        entries.forEach(planes -> {
+            counts[BakePlane.PLANES.length]++;
+            for (BakePlane plane : BakePlane.PLANES) {
+                if (planes.planeIfPresent(plane) != null) {
+                    counts[plane.ordinal()]++;
+                }
+            }
+        });
+        return counts;
+    }
+
+    public ChunkPlanes planes(int chunkX, int chunkZ) {
+        ConcurrentClockCache<ChunkPlanes> current = entries;
+        long key = key(chunkX, chunkZ);
+        ChunkPlanes existing = current.get(key);
+        return existing != null ? existing : current.putIfAbsent(key, new ChunkPlanes(chunkX, chunkZ));
+    }
+
+    public ChunkPlanes planesIfPresent(int chunkX, int chunkZ) {
+        return entries.get(key(chunkX, chunkZ));
+    }
+
+    public ChunkPlanes.Plane planeIfPresent(BakePlane plane, int chunkX, int chunkZ) {
+        long key = key(chunkX, chunkZ);
+        Recent last = recent.get();
+        ConcurrentClockCache<ChunkPlanes> current = entries;
+        ChunkPlanes planes;
+        if (last.key == key && last.entries == current) {
+            planes = last.planes;
+        } else {
+            planes = current.get(key);
+            if (planes == null) {
+                return null;
+            }
+            last.key = key;
+            last.planes = planes;
+            last.entries = current;
+        }
+        return planes.planeIfPresent(plane);
+    }
+
+    public ChunkPlanes.Plane plane(BakePlane plane, int chunkX, int chunkZ) {
+        return planes(chunkX, chunkZ).plane(plane);
+    }
+
+    public Object complete(BakePlane plane, int chunkX, int chunkZ) {
+        return remembered(chunkX, chunkZ).complete(plane, source);
+    }
+
+    public boolean memoAllowed() {
+        return SPARSE.get()[0] == 0 && !source.mainThread();
+    }
+
+    public void storeDouble(BakePlane plane, int blockX, int blockZ, double value, long revision) {
+        if (revision != ProvisionalSampling.revision()) {
+            return;
+        }
+        remembered(blockX >> 4, blockZ >> 4).plane(plane).storeDouble(((blockZ & 15) << 4) | (blockX & 15), value);
+    }
+
+    public void storeObject(BakePlane plane, int blockX, int blockZ, Object value, long revision) {
+        if (revision != ProvisionalSampling.revision()) {
+            return;
+        }
+        remembered(blockX >> 4, blockZ >> 4).plane(plane).storeObject(((blockZ & 15) << 4) | (blockX & 15), value);
+    }
+
+    private ChunkPlanes remembered(int chunkX, int chunkZ) {
+        ConcurrentClockCache<ChunkPlanes> current = entries;
+        long key = key(chunkX, chunkZ);
+        ChunkPlanes existing = current.get(key);
+        ChunkPlanes planes = existing != null ? existing : current.putIfAbsent(key, new ChunkPlanes(chunkX, chunkZ));
+        Recent last = recent.get();
+        last.key = key;
+        last.planes = planes;
+        last.entries = current;
+        return planes;
+    }
+
+    public static void enterSparse() {
+        SPARSE.get()[0]++;
+    }
+
+    public static void exitSparse() {
+        SPARSE.get()[0]--;
+    }
+
+    public static boolean inSparseScope() {
+        return SPARSE.get()[0] > 0;
+    }
+
+    public static long key(int chunkX, int chunkZ) {
+        return ((long) chunkX << 32) ^ (chunkZ & 0xffffffffL);
+    }
+
+    private static final class Recent {
+        private long key;
+        private ChunkPlanes planes;
+        private ConcurrentClockCache<ChunkPlanes> entries;
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/bake/ChunkPlanes.java b/core/src/main/java/art/arcane/iris/generation/bake/ChunkPlanes.java
new file mode 100644
index 000000000..6a72dd756
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/bake/ChunkPlanes.java
@@ -0,0 +1,208 @@
+package art.arcane.iris.generation.bake;
+
+import art.arcane.iris.generation.stream.ProvisionalSampling;
+
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.VarHandle;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.concurrent.atomic.AtomicReferenceArray;
+
+public final class ChunkPlanes {
+    private static final VarHandle READY = MethodHandles.arrayElementVarHandle(long[].class);
+
+    private final int chunkX;
+    private final int chunkZ;
+    private final AtomicReferenceArray<Plane> planes = new AtomicReferenceArray<>(BakePlane.PLANES.length);
+    private volatile ColumnBake columnBake;
+
+    ChunkPlanes(int chunkX, int chunkZ) {
+        this.chunkX = chunkX;
+        this.chunkZ = chunkZ;
+    }
+
+    public int chunkX() {
+        return chunkX;
+    }
+
+    public int chunkZ() {
+        return chunkZ;
+    }
+
+    public Plane planeIfPresent(BakePlane kind) {
+        return planes.getAcquire(kind.ordinal());
+    }
+
+    public Plane plane(BakePlane kind) {
+        int slot = kind.ordinal();
+        Plane plane = planes.getAcquire(slot);
+        if (plane != null) {
+            return plane;
+        }
+        Plane created = new Plane(kind);
+        Plane witness = planes.compareAndExchangeRelease(slot, null, created);
+        return witness == null ? created : witness;
+    }
+
+    Object complete(BakePlane kind, PlaneSource source) {
+        Plane plane = plane(kind);
+        while (true) {
+            if (plane.complete) {
+                return plane.values;
+            }
+            Pending running = plane.filling.get();
+            if (running != null) {
+                if (running.owner == Thread.currentThread()) {
+                    return plane.unpublishedFill(source, chunkX, chunkZ);
+                }
+                running.await();
+                continue;
+            }
+            Pending pending = new Pending(Thread.currentThread());
+            if (!plane.filling.compareAndSet(null, pending)) {
+                continue;
+            }
+            try {
+                return plane.fill(source, chunkX, chunkZ);
+            } finally {
+                plane.filling.set(null);
+                pending.complete();
+            }
+        }
+    }
+
+    ColumnBake columnBake() {
+        return columnBake;
+    }
+
+    ColumnBake columnBake(PlaneSource source) {
+        ColumnBake bake = columnBake;
+        if (bake != null) {
+            return bake;
+        }
+        long revision = ProvisionalSampling.revision();
+        bake = source.assemble(this);
+        if (revision == ProvisionalSampling.revision()) {
+            columnBake = bake;
+        }
+        return bake;
+    }
+
+    public static final class Plane {
+        private final BakePlane kind;
+        private final Object values;
+        private final long[] ready = new long[4];
+        private final AtomicReference<Pending> filling = new AtomicReference<>();
+        private volatile boolean complete;
+
+        private Plane(BakePlane kind) {
+            this.kind = kind;
+            this.values = kind.doubles() ? new double[256] : new Object[256];
+        }
+
+        public boolean ready(int index) {
+            return complete || ((long) READY.getAcquire(ready, index >>> 6) & (1L << (index & 63))) != 0L;
+        }
+
+        public double doubleAt(int index) {
+            return ((double[]) values)[index];
+        }
+
+        public Object objectAt(int index) {
+            return ((Object[]) values)[index];
+        }
+
+        public void storeDouble(int index, double value) {
+            ((double[]) values)[index] = value;
+            markReady(index);
+        }
+
+        public void storeObject(int index, Object value) {
+            ((Object[]) values)[index] = value;
+            markReady(index);
+        }
+
+        private void markReady(int index) {
+            READY.getAndBitwiseOrRelease(ready, index >>> 6, 1L << (index & 63));
+        }
+
+        private long[] missing() {
+            long[] missing = new long[4];
+            for (int word = 0; word < 4; word++) {
+                missing[word] = ~(long) READY.getAcquire(ready, word);
+            }
+            return missing;
+        }
+
+        private Object fill(PlaneSource source, int chunkX, int chunkZ) {
+            long[] missing = missing();
+            Object computed = kind.doubles() ? new double[256] : new Object[256];
+            long revision = ProvisionalSampling.revision();
+            source.fill(kind, chunkX, chunkZ, missing, computed);
+            if (revision != ProvisionalSampling.revision()) {
+                return merge(missing, computed);
+            }
+            for (int index = 0; index < 256; index++) {
+                if ((missing[index >>> 6] & (1L << (index & 63))) != 0L) {
+                    if (kind.doubles()) {
+                        ((double[]) values)[index] = ((double[]) computed)[index];
+                    } else {
+                        ((Object[]) values)[index] = ((Object[]) computed)[index];
+                    }
+                }
+            }
+            for (int word = 0; word < 4; word++) {
+                READY.setRelease(ready, word, -1L);
+            }
+            complete = true;
+            return values;
+        }
+
+        private Object unpublishedFill(PlaneSource source, int chunkX, int chunkZ) {
+            long[] missing = missing();
+            Object computed = kind.doubles() ? new double[256] : new Object[256];
+            source.fill(kind, chunkX, chunkZ, missing, computed);
+            return merge(missing, computed);
+        }
+
+        private Object merge(long[] missing, Object computed) {
+            for (int index = 0; index < 256; index++) {
+                if ((missing[index >>> 6] & (1L << (index & 63))) == 0L) {
+                    if (kind.doubles()) {
+                        ((double[]) computed)[index] = ((double[]) values)[index];
+                    } else {
+                        ((Object[]) computed)[index] = ((Object[]) values)[index];
+                    }
+                }
+            }
+            return computed;
+        }
+    }
+
+    private static final class Pending {
+        private final Thread owner;
+        private boolean done;
+
+        private Pending(Thread owner) {
+            this.owner = owner;
+        }
+
+        private synchronized void complete() {
+            done = true;
+            notifyAll();
+        }
+
+        private synchronized void await() {
+            boolean interrupted = false;
+            while (!done) {
+                try {
+                    wait();
+                } catch (InterruptedException e) {
+                    interrupted = true;
+                }
+            }
+            if (interrupted) {
+                Thread.currentThread().interrupt();
+            }
+        }
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/bake/ColumnBake.java b/core/src/main/java/art/arcane/iris/generation/bake/ColumnBake.java
new file mode 100644
index 000000000..749263925
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/bake/ColumnBake.java
@@ -0,0 +1,55 @@
+package art.arcane.iris.generation.bake;
+
+import art.arcane.iris.generation.terrain.Terrain3DColumn;
+
+public final class ColumnBake {
+    public static final int APRON_WIDTH = 18;
+
+    public final int chunkX;
+    public final int chunkZ;
+    public final short[] regionId;
+    public final short[] baseBiomeId;
+    public final short[] trueBiomeId;
+    public final short[] caveBiomeId;
+    public final double[] baseHeight;
+    public final double[] naturalHeight;
+    public final double[] height;
+    public final int[] roundedHeight;
+    public final float[] fluidSurface;
+    public final short[] rockState;
+    public final short[] fluidState;
+    public final Terrain3DColumn[] terrainColumns;
+    public final double[] apronHeight;
+
+    public ColumnBake(Planes planes) {
+        this.chunkX = planes.chunkX();
+        this.chunkZ = planes.chunkZ();
+        this.regionId = planes.regionId();
+        this.baseBiomeId = planes.baseBiomeId();
+        this.trueBiomeId = planes.trueBiomeId();
+        this.caveBiomeId = planes.caveBiomeId();
+        this.baseHeight = planes.baseHeight();
+        this.naturalHeight = planes.naturalHeight();
+        this.height = planes.height();
+        this.roundedHeight = planes.roundedHeight();
+        this.fluidSurface = planes.fluidSurface();
+        this.rockState = planes.rockState();
+        this.fluidState = planes.fluidState();
+        this.terrainColumns = planes.terrainColumns();
+        this.apronHeight = planes.apronHeight();
+    }
+
+    public static int index(int localX, int localZ) {
+        return (localZ << 4) | localX;
+    }
+
+    public static int apronIndex(int localX, int localZ) {
+        return (localZ + 1) * APRON_WIDTH + localX + 1;
+    }
+
+    public record Planes(int chunkX, int chunkZ, short[] regionId, short[] baseBiomeId, short[] trueBiomeId,
+                         short[] caveBiomeId, double[] baseHeight, double[] naturalHeight, double[] height,
+                         int[] roundedHeight, float[] fluidSurface, short[] rockState, short[] fluidState,
+                         Terrain3DColumn[] terrainColumns, double[] apronHeight) {
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/bake/GeneratorEvaluations.java b/core/src/main/java/art/arcane/iris/generation/bake/GeneratorEvaluations.java
new file mode 100644
index 000000000..7466bed71
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/bake/GeneratorEvaluations.java
@@ -0,0 +1,48 @@
+package art.arcane.iris.generation.bake;
+
+import java.util.concurrent.atomic.LongAdder;
+
+public final class GeneratorEvaluations {
+    private static final LongAdder BAKED_CHUNKS = new LongAdder();
+    private static final LongAdder BAKED = new LongAdder();
+    private static final LongAdder BATCHED = new LongAdder();
+    private static final LongAdder SCALAR = new LongAdder();
+
+    private GeneratorEvaluations() {
+    }
+
+    public static void bakedChunk(long evaluations) {
+        BAKED_CHUNKS.increment();
+        BAKED.add(evaluations);
+    }
+
+    public static void batched(long evaluations) {
+        BATCHED.add(evaluations);
+    }
+
+    public static void scalar(int evaluations) {
+        SCALAR.add(evaluations);
+    }
+
+    public static Snapshot snapshot() {
+        return new Snapshot(BAKED_CHUNKS.sum(), BAKED.sum(), BATCHED.sum(), SCALAR.sum());
+    }
+
+    public static void reset() {
+        BAKED_CHUNKS.reset();
+        BAKED.reset();
+        BATCHED.reset();
+        SCALAR.reset();
+    }
+
+    public record Snapshot(long bakedChunks, long bakedEvaluations, long batchedEvaluations, long scalarEvaluations) {
+        public double bakedEvaluationsPerChunk() {
+            return bakedChunks == 0L ? 0D : (double) bakedEvaluations / bakedChunks;
+        }
+
+        public Snapshot minus(Snapshot earlier) {
+            return new Snapshot(bakedChunks - earlier.bakedChunks, bakedEvaluations - earlier.bakedEvaluations,
+                    batchedEvaluations - earlier.batchedEvaluations, scalarEvaluations - earlier.scalarEvaluations);
+        }
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/bake/PlaneSource.java b/core/src/main/java/art/arcane/iris/generation/bake/PlaneSource.java
new file mode 100644
index 000000000..5e98ffd08
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/bake/PlaneSource.java
@@ -0,0 +1,9 @@
+package art.arcane.iris.generation.bake;
+
+public interface PlaneSource {
+    void fill(BakePlane plane, int chunkX, int chunkZ, long[] missing, Object values);
+
+    ColumnBake assemble(ChunkPlanes planes);
+
+    boolean mainThread();
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/bake/TerrainProgram.java b/core/src/main/java/art/arcane/iris/generation/bake/TerrainProgram.java
new file mode 100644
index 000000000..a67f63719
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/bake/TerrainProgram.java
@@ -0,0 +1,161 @@
+package art.arcane.iris.generation.bake;
+
+import art.arcane.iris.generation.noise.GeneratorProgram;
+import art.arcane.iris.generation.noise.IrisGenerator;
+import art.arcane.iris.generation.noise.TerrainBatchScratch;
+import art.arcane.volmlib.util.math.M;
+
+import java.util.Arrays;
+
+public final class TerrainProgram {
+    private static final int SKIPPED = 0;
+    private static final int CONSTANT = 1;
+    private static final int ACTIVE = 2;
+
+    private final IrisGenerator[][] generators;
+    private final GeneratorProgram[][] programs;
+    private final long heightSeed;
+
+    private TerrainProgram(IrisGenerator[][] generators, GeneratorProgram[][] programs, long heightSeed) {
+        this.generators = generators;
+        this.programs = programs;
+        this.heightSeed = heightSeed;
+    }
+
+    public static TerrainProgram compile(IrisGenerator[][] generators, long heightSeed) {
+        GeneratorProgram[][] programs = new GeneratorProgram[generators.length][];
+        for (int group = 0; group < generators.length; group++) {
+            programs[group] = new GeneratorProgram[generators[group].length];
+            for (int index = 0; index < generators[group].length; index++) {
+                IrisGenerator generator = generators[group][index];
+                programs[group][index] = generator.supportsBatch() ? generator.compileProgram(heightSeed) : null;
+            }
+        }
+        return new TerrainProgram(generators, programs, heightSeed);
+    }
+
+    public long heightSeed() {
+        return heightSeed;
+    }
+
+    public double average(int group, TerrainBatchScratch scratch, double low, double high, double x, double z) {
+        IrisGenerator[] members = generators[group];
+        if (members.length == 0) {
+            return 0D;
+        }
+        if (!Double.isFinite(low) || !Double.isFinite(high)) {
+            throw new IllegalStateException("Terrain generator bounds were not finite at " + x + "," + z
+                    + " (generator=" + members[0].getLoadKey() + ", bounds=" + low + ".." + high + ").");
+        }
+        double height = 0D;
+        if (low == high) {
+            for (int member = 0; member < members.length; member++) {
+                height += low;
+            }
+            return height / members.length;
+        }
+        GeneratorEvaluations.scalar(members.length);
+        GeneratorProgram[] compiled = programs[group];
+        for (int member = 0; member < members.length; member++) {
+            GeneratorProgram program = compiled[member];
+            double noise = program != null ? program.height(scratch, x, z) : members[member].getHeight(x, z, heightSeed);
+            if (!Double.isFinite(noise)) {
+                throw new IllegalStateException("Terrain generator noise was not finite at " + x + "," + z
+                        + " (generator=" + members[member].getLoadKey() + ", noise=" + noise
+                        + ", bounds=" + low + ".." + high + ").");
+            }
+            height += M.lerp(low, high, noise);
+        }
+        return height / members.length;
+    }
+
+    public int groups() {
+        return generators.length;
+    }
+
+    public int groupSize(int group) {
+        return generators[group].length;
+    }
+
+    public long accumulate(int group, TerrainBatchScratch scratch, double[] xs, double[] zs, int count,
+                           double[] lows, double[] highs, double[] heights) {
+        IrisGenerator[] members = generators[group];
+        if (members.length == 0 || count == 0) {
+            return 0L;
+        }
+        int mark = scratch.mark();
+        int indexMark = scratch.indexMark();
+        int[] modes = scratch.indices(count);
+        int activeCount = 0;
+        for (int index = 0; index < count; index++) {
+            double low = lows[index];
+            double high = highs[index];
+            if (low == 0D && high == 0D) {
+                modes[index] = SKIPPED;
+                continue;
+            }
+            if (!Double.isFinite(low) || !Double.isFinite(high)) {
+                throw new IllegalStateException("Terrain generator bounds were not finite at " + xs[index] + "," + zs[index]
+                        + " (generator=" + members[0].getLoadKey() + ", bounds=" + low + ".." + high + ").");
+            }
+            if (low == high) {
+                modes[index] = CONSTANT;
+                double sum = 0D;
+                for (int member = 0; member < members.length; member++) {
+                    sum += low;
+                }
+                heights[index] += sum / members.length;
+                continue;
+            }
+            modes[index] = ACTIVE;
+            activeCount++;
+        }
+        if (activeCount == 0) {
+            scratch.resetIndices(indexMark);
+            return 0L;
+        }
+        double[] activeX = scratch.buffer(activeCount);
+        double[] activeZ = scratch.buffer(activeCount);
+        double[] activeLow = scratch.buffer(activeCount);
+        double[] activeHigh = scratch.buffer(activeCount);
+        int[] activeIndex = scratch.indices(activeCount);
+        int cursor = 0;
+        for (int index = 0; index < count; index++) {
+            if (modes[index] == ACTIVE) {
+                activeX[cursor] = xs[index];
+                activeZ[cursor] = zs[index];
+                activeLow[cursor] = lows[index];
+                activeHigh[cursor] = highs[index];
+                activeIndex[cursor++] = index;
+            }
+        }
+        double[] sums = scratch.buffer(activeCount);
+        double[] noise = scratch.buffer(activeCount);
+        Arrays.fill(sums, 0, activeCount, 0D);
+        GeneratorProgram[] compiled = programs[group];
+        for (int member = 0; member < members.length; member++) {
+            GeneratorProgram program = compiled[member];
+            if (program != null) {
+                program.heights(scratch, activeX, activeZ, activeCount, noise);
+            } else {
+                for (int index = 0; index < activeCount; index++) {
+                    noise[index] = members[member].getHeight(activeX[index], activeZ[index], heightSeed);
+                }
+            }
+            for (int index = 0; index < activeCount; index++) {
+                if (!Double.isFinite(noise[index])) {
+                    throw new IllegalStateException("Terrain generator noise was not finite at " + activeX[index] + "," + activeZ[index]
+                            + " (generator=" + members[member].getLoadKey() + ", noise=" + noise[index]
+                            + ", bounds=" + activeLow[index] + ".." + activeHigh[index] + ").");
+                }
+                sums[index] += M.lerp(activeLow[index], activeHigh[index], noise[index]);
+            }
+        }
+        for (int index = 0; index < activeCount; index++) {
+            heights[activeIndex[index]] += sums[index] / members.length;
+        }
+        scratch.reset(mark);
+        scratch.resetIndices(indexMark);
+        return (long) activeCount * members.length;
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/biome/IrisBiome.java b/core/src/main/java/art/arcane/iris/generation/biome/IrisBiome.java
index e70c2ef91..b1e0cd05e 100644
--- a/core/src/main/java/art/arcane/iris/generation/biome/IrisBiome.java
+++ b/core/src/main/java/art/arcane/iris/generation/biome/IrisBiome.java
@@ -515,7 +515,10 @@ public class IrisBiome extends IrisRegistrant implements Rarity {
     }
 
     public CNG getChildrenGenerator(RNG random, int sig, double scale) {
-        long seed = deriveChildStyleSeed(random, sig).getSeed();
+        return getChildrenGenerator(deriveChildStyleSeed(random, sig).getSeed(), scale);
+    }
+
+    public CNG getChildrenGenerator(long seed, double scale) {
         IrisData data = getLoader();
         Engine engine = data == null ? null : data.getEngine();
         CachedChildGenerator recent = recentChildGenerator;
@@ -533,6 +536,10 @@ public class IrisBiome extends IrisRegistrant implements Rarity {
         return random.nextParallelRNG(signature * CHILDREN_SEED_SALT);
     }
 
+    public static long childStyleSeed(RNG random, int signature) {
+        return deriveChildStyleSeed(random, signature).getSeed();
+    }
+
     public KList<NativeBlockState> generateLayers(IrisDimension dim, double wx, double wz, RNG random, int maxDepth, int height, IrisData rdata, IrisComplex complex) {
         return IrisBiomeLayerGenerator.generateLayers(this, dim, wx, wz, random, maxDepth, height, rdata, complex);
     }
diff --git a/core/src/main/java/art/arcane/iris/generation/mantle/CaveObjectPlacementTransaction.java b/core/src/main/java/art/arcane/iris/generation/mantle/CaveObjectPlacementTransaction.java
index b53862f49..e8a47f754 100644
--- a/core/src/main/java/art/arcane/iris/generation/mantle/CaveObjectPlacementTransaction.java
+++ b/core/src/main/java/art/arcane/iris/generation/mantle/CaveObjectPlacementTransaction.java
@@ -30,27 +30,41 @@ import art.arcane.iris.generation.hydrology.cave.HydrologyCaveCell;
 import art.arcane.volmlib.nativelib.terrain.NativeBlockState;
 import art.arcane.volmlib.util.math.BlockPosition;
 import art.arcane.iris.generation.block.B;
-import art.arcane.volmlib.util.collection.KList;
 import it.unimi.dsi.fastutil.longs.Long2IntOpenHashMap;
+import it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap;
 import org.jetbrains.annotations.Nullable;
 
-import java.util.HashMap;
-import java.util.Map;
+import java.util.Arrays;
 
 final class CaveObjectPlacementTransaction implements IObjectPlacer {
     private static final int CACHE_MISS = Integer.MIN_VALUE;
+    private static final int POSITION_BITS = 21;
+    private static final int POSITION_LIMIT = 1 << (POSITION_BITS - 1);
+    private static final long POSITION_MASK = (1L << POSITION_BITS) - 1L;
 
     private final IObjectPlacer delegate;
     private final Engine engine;
     private final int anchorY;
     private final int minDepthBelowSurface;
     private final int worldHeight;
-    private final KList<BufferedMutation> mutations;
-    private final Map<PositionKey, NativeBlockState> bufferedBlocks;
+    private static final byte BLOCK = 0;
+    private static final byte TILE = 1;
+    private static final byte DATA = 2;
+    private int[] mutationX = new int[64];
+    private int[] mutationY = new int[64];
+    private int[] mutationZ = new int[64];
+    private Object[] mutationValues = new Object[64];
+    private byte[] mutationKinds = new byte[64];
+    private boolean[] mutationCanopies = new boolean[64];
+    private int mutationCount;
+    private final Long2ObjectOpenHashMap<NativeBlockState> bufferedBlocks;
     private final Long2IntOpenHashMap surfaceHeights;
     private final Long2IntOpenHashMap caveCeilings;
     private int blockWrites;
     private BlockPosition canopyPosition;
+    private boolean originKnown;
+    private int originX;
+    private int originZ;
 
     CaveObjectPlacementTransaction(IObjectPlacer delegate, int anchorY, int minDepthBelowSurface) {
         this.delegate = delegate;
@@ -58,8 +72,7 @@ final class CaveObjectPlacementTransaction implements IObjectPlacer {
         this.anchorY = anchorY;
         this.minDepthBelowSurface = Math.max(0, minDepthBelowSurface);
         this.worldHeight = engine == null ? 0 : engine.getHeight();
-        this.mutations = new KList<>();
-        this.bufferedBlocks = new HashMap<>();
+        this.bufferedBlocks = new Long2ObjectOpenHashMap<>();
         this.surfaceHeights = new Long2IntOpenHashMap();
         this.caveCeilings = new Long2IntOpenHashMap();
         this.surfaceHeights.defaultReturnValue(CACHE_MISS);
@@ -73,28 +86,41 @@ final class CaveObjectPlacementTransaction implements IObjectPlacer {
         }
 
         IrisComplex complex = engine == null ? null : engine.getComplex();
-        for (BufferedMutation mutation : mutations) {
+        boolean previousChecked = false;
+        int previousX = 0;
+        int previousY = 0;
+        int previousZ = 0;
+        for (int index = 0; index < mutationCount; index++) {
+            int x = mutationX[index];
+            int y = mutationY[index];
+            int z = mutationZ[index];
+            if (previousChecked && x == previousX && y == previousY && z == previousZ) {
+                continue;
+            }
             if (complex != null
-                    && !complex.allowsNewDiscreteContentAt(mutation.x(), mutation.z())) {
+                    && !complex.allowsNewDiscreteContentAt(x, z)) {
                 discard();
                 return CommitResult.REJECTED_TRANSITION;
             }
-            if (!isWithinBounds(mutation.x(), mutation.y(), mutation.z())) {
+            if (!isWithinBounds(x, y, z)) {
                 discard();
                 return CommitResult.REJECTED_BOUNDS;
             }
-            SubterrainCell feature = engine.getSubterrainCell(mutation.x(), mutation.y(), mutation.z());
+            SubterrainCell feature = engine.getSubterrainCell(x, y, z);
             if (SubterrainRasterizer.protectsPlacement(feature)
-                    || feature != null && feature.solid() && delegate.isSolid(mutation.x(), mutation.y(), mutation.z())) {
+                    || feature != null && feature.solid() && delegate.isSolid(x, y, z)) {
                 discard();
                 return CommitResult.REJECTED_SUBTERRAIN;
             }
-            HydrologyCaveCell hydrology = delegate.getData(
-                    mutation.x(), mutation.y(), mutation.z(), HydrologyCaveCell.class);
+            HydrologyCaveCell hydrology = delegate.getData(x, y, z, HydrologyCaveCell.class);
             if (hydrology != null && hydrology.protectsPlacement()) {
                 discard();
                 return CommitResult.REJECTED_HYDROLOGY;
             }
+            previousChecked = true;
+            previousX = x;
+            previousY = y;
+            previousZ = z;
         }
 
         applyMutations();
@@ -106,18 +132,26 @@ final class CaveObjectPlacementTransaction implements IObjectPlacer {
         boolean canopyOpen = false;
         boolean skipCanopy = false;
         try {
-            for (BufferedMutation mutation : mutations) {
-                if (mutation.value() instanceof NativeBlockState) {
+            for (int index = 0; index < mutationCount; index++) {
+                int x = mutationX[index];
+                int y = mutationY[index];
+                int z = mutationZ[index];
+                Object value = mutationValues[index];
+                boolean canopy = mutationCanopies[index];
+                if (value instanceof NativeBlockState) {
                     if (canopyOpen) {
                         delegate.endTreeCanopy();
                         canopyOpen = false;
                     }
-                    skipCanopy = mutation.canopy()
-                            && !delegate.beginTreeCanopy(new BlockPosition(mutation.x(), mutation.y(), mutation.z()));
-                    canopyOpen = mutation.canopy() && !skipCanopy;
+                    skipCanopy = canopy && !delegate.beginTreeCanopy(new BlockPosition(x, y, z));
+                    canopyOpen = canopy && !skipCanopy;
                 }
-                if (!mutation.canopy() || !skipCanopy) {
-                    mutation.apply(delegate);
+                if (!canopy || !skipCanopy) {
+                    switch (mutationKinds[index]) {
+                        case BLOCK -> delegate.set(x, y, z, (NativeBlockState) value);
+                        case TILE -> delegate.setTile(x, y, z, (TileData) value);
+                        default -> delegate.setData(x, y, z, value);
+                    }
                 }
             }
         } finally {
@@ -128,11 +162,31 @@ final class CaveObjectPlacementTransaction implements IObjectPlacer {
     }
 
     void discard() {
-        mutations.clear();
+        Arrays.fill(mutationValues, 0, mutationCount, null);
+        mutationCount = 0;
         bufferedBlocks.clear();
         blockWrites = 0;
     }
 
+    private void buffer(byte kind, int x, int y, int z, Object value) {
+        if (mutationCount == mutationValues.length) {
+            int capacity = mutationCount * 2;
+            mutationX = Arrays.copyOf(mutationX, capacity);
+            mutationY = Arrays.copyOf(mutationY, capacity);
+            mutationZ = Arrays.copyOf(mutationZ, capacity);
+            mutationValues = Arrays.copyOf(mutationValues, capacity);
+            mutationKinds = Arrays.copyOf(mutationKinds, capacity);
+            mutationCanopies = Arrays.copyOf(mutationCanopies, capacity);
+        }
+        mutationX[mutationCount] = x;
+        mutationY[mutationCount] = y;
+        mutationZ[mutationCount] = z;
+        mutationValues[mutationCount] = value;
+        mutationKinds[mutationCount] = kind;
+        mutationCanopies[mutationCount] = isCanopy(x, y, z);
+        mutationCount++;
+    }
+
     int getCaveCeiling(int x, int z) {
         long key = Cache.key(x, z);
         int cached = caveCeilings.get(key);
@@ -164,8 +218,8 @@ final class CaveObjectPlacementTransaction implements IObjectPlacer {
         if (state == null) {
             return;
         }
-        mutations.add(new BlockMutation(x, y, z, state, isCanopy(x, y, z)));
-        bufferedBlocks.put(new PositionKey(x, y, z), state);
+        buffer(BLOCK, x, y, z, state);
+        bufferedBlocks.put(bufferKey(x, y, z), state);
         blockWrites++;
     }
 
@@ -190,7 +244,7 @@ final class CaveObjectPlacementTransaction implements IObjectPlacer {
 
     @Override
     public NativeBlockState get(int x, int y, int z) {
-        NativeBlockState buffered = bufferedBlocks.get(new PositionKey(x, y, z));
+        NativeBlockState buffered = bufferedBlocks.isEmpty() ? null : bufferedBlocks.get(bufferKey(x, y, z));
         return buffered == null ? delegate.get(x, y, z) : buffered;
     }
 
@@ -211,7 +265,7 @@ final class CaveObjectPlacementTransaction implements IObjectPlacer {
 
     @Override
     public boolean isSolid(int x, int y, int z) {
-        NativeBlockState buffered = bufferedBlocks.get(new PositionKey(x, y, z));
+        NativeBlockState buffered = bufferedBlocks.isEmpty() ? null : bufferedBlocks.get(bufferKey(x, y, z));
         return buffered == null ? delegate.isSolid(x, y, z) : B.isSolid(buffered);
     }
 
@@ -242,7 +296,7 @@ final class CaveObjectPlacementTransaction implements IObjectPlacer {
     @Override
     public void setTile(int x, int y, int z, TileData tile) {
         if (tile != null) {
-            mutations.add(new TileMutation(x, y, z, tile, isCanopy(x, y, z)));
+            buffer(TILE, x, y, z, tile);
         }
     }
 
@@ -251,21 +305,20 @@ final class CaveObjectPlacementTransaction implements IObjectPlacer {
         if (data == null) {
             return;
         }
-        mutations.add(new DataMutation(x, y, z, data, isCanopy(x, y, z)));
+        buffer(DATA, x, y, z, data);
         if (data instanceof NativeBlockState state) {
-            bufferedBlocks.put(new PositionKey(x, y, z), state);
+            bufferedBlocks.put(bufferKey(x, y, z), state);
             blockWrites++;
         }
     }
 
     @Override
     public <T> @Nullable T getData(int x, int y, int z, Class<T> type) {
-        for (int i = mutations.size() - 1; i >= 0; i--) {
-            BufferedMutation mutation = mutations.get(i);
-            if (mutation.x() != x || mutation.y() != y || mutation.z() != z) {
+        for (int index = mutationCount - 1; index >= 0; index--) {
+            if (mutationX[index] != x || mutationY[index] != y || mutationZ[index] != z) {
                 continue;
             }
-            Object value = mutation.value();
+            Object value = mutationValues[index];
             if (type.isInstance(value)) {
                 return type.cast(value);
             }
@@ -278,6 +331,22 @@ final class CaveObjectPlacementTransaction implements IObjectPlacer {
         return engine;
     }
 
+    private long bufferKey(int x, int y, int z) {
+        if (!originKnown) {
+            originX = x;
+            originZ = z;
+            originKnown = true;
+        }
+        int dx = x - originX;
+        int dz = z - originZ;
+        if (dx < -POSITION_LIMIT || dx >= POSITION_LIMIT || dz < -POSITION_LIMIT || dz >= POSITION_LIMIT
+                || y < -POSITION_LIMIT || y >= POSITION_LIMIT) {
+            throw new IllegalStateException("Cave object write at " + x + "," + y + "," + z
+                    + " is too far from its first write at " + originX + "," + originZ);
+        }
+        return ((dx & POSITION_MASK) << (POSITION_BITS * 2)) | ((dz & POSITION_MASK) << POSITION_BITS) | (y & POSITION_MASK);
+    }
+
     private boolean isWithinBounds(int x, int y, int z) {
         if (engine == null || y < 0 || y >= worldHeight) {
             return false;
@@ -325,42 +394,4 @@ final class CaveObjectPlacementTransaction implements IObjectPlacer {
         REJECTED_HYDROLOGY,
         REJECTED_SUBTERRAIN
     }
-
-    private interface BufferedMutation {
-        int x();
-
-        int y();
-
-        int z();
-
-        Object value();
-
-        boolean canopy();
-
-        void apply(IObjectPlacer placer);
-    }
-
-    private record BlockMutation(int x, int y, int z, NativeBlockState value, boolean canopy) implements BufferedMutation {
-        @Override
-        public void apply(IObjectPlacer placer) {
-            placer.set(x, y, z, value);
-        }
-    }
-
-    private record TileMutation(int x, int y, int z, TileData value, boolean canopy) implements BufferedMutation {
-        @Override
-        public void apply(IObjectPlacer placer) {
-            placer.setTile(x, y, z, value);
-        }
-    }
-
-    private record DataMutation(int x, int y, int z, Object value, boolean canopy) implements BufferedMutation {
-        @Override
-        public void apply(IObjectPlacer placer) {
-            placer.setData(x, y, z, value);
-        }
-    }
-
-    private record PositionKey(int x, int y, int z) {
-    }
 }
diff --git a/core/src/main/java/art/arcane/iris/generation/mantle/MantleObjectComponent.java b/core/src/main/java/art/arcane/iris/generation/mantle/MantleObjectComponent.java
index 913c726f8..3d452b5ab 100644
--- a/core/src/main/java/art/arcane/iris/generation/mantle/MantleObjectComponent.java
+++ b/core/src/main/java/art/arcane/iris/generation/mantle/MantleObjectComponent.java
@@ -88,6 +88,8 @@ public class MantleObjectComponent extends IrisMantleComponent {
     private static final Map<String, CaveRejectLogState> CAVE_REJECT_LOG_STATE = new ConcurrentHashMap<>();
     private static final Set<String> MISSING_LOAD_KEY_WARNED = ConcurrentHashMap.newKeySet();
     private static final long SOURCE_PLAN_STATS_INTERVAL_MS = 30_000L;
+    private static final int MAXIMUM_TREE_MATERIALS = 8192;
+    private static final Map<NativeBlockState, TreeBlockMaterial> TREE_MATERIALS = new ConcurrentHashMap<>();
 
     private final Object collisionRuleLock;
     private final ObjectSourcePlanCache sourcePlans;
@@ -124,7 +126,14 @@ public class MantleObjectComponent extends IrisMantleComponent {
     }
 
     private static void writeTreeMaterial(IObjectPlacer placer, int x, int y, int z, NativeBlockState data) {
-        placer.setData(x, y, z, TreeBlockMaterial.of(data));
+        TreeBlockMaterial material = TREE_MATERIALS.get(data);
+        if (material == null) {
+            material = TreeBlockMaterial.of(data);
+            if (TREE_MATERIALS.size() < MAXIMUM_TREE_MATERIALS) {
+                TREE_MATERIALS.putIfAbsent(data, material);
+            }
+        }
+        placer.setData(x, y, z, material);
     }
 
     @Override
@@ -157,19 +166,23 @@ public class MantleObjectComponent extends IrisMantleComponent {
         ObjectDestinationTransaction transaction = new ObjectDestinationTransaction(writer, x, z);
         int radius = getRadius();
         int sourceChunkRadius = sourceChunkRadius(radius);
-        replaySourceChunks(
-                x,
-                z,
-                radius,
-                (sourceX, sourceZ) -> {
-                    ObjectSourcePlan plan = sourcePlans.acquire(sourceX, sourceZ, x, z, sourceChunkRadius,
-                            () -> buildSourcePlan(writer, sourceX, sourceZ, context));
-                    if (plan != null) {
-                        transaction.apply(plan);
-                        plan.persistContinuations(writer, sourceX, sourceZ, x, z);
-                    }
-                }
-        );
+        int side = (sourceChunkRadius * 2) + 1;
+        ObjectSourcePlan[] plans = new ObjectSourcePlan[side * side];
+        int[] slot = new int[1];
+        replaySourceChunks(x, z, radius, (sourceX, sourceZ) -> plans[slot[0]++] = sourcePlans.tryAcquire(
+                sourceX, sourceZ, x, z, sourceChunkRadius, () -> buildSourcePlan(writer, sourceX, sourceZ, context)));
+        slot[0] = 0;
+        replaySourceChunks(x, z, radius, (sourceX, sourceZ) -> {
+            ObjectSourcePlan plan = plans[slot[0]++];
+            if (plan == ObjectSourcePlanCache.BUSY) {
+                plan = sourcePlans.acquire(sourceX, sourceZ, x, z, sourceChunkRadius,
+                        () -> buildSourcePlan(writer, sourceX, sourceZ, context));
+            }
+            if (plan != null) {
+                transaction.apply(plan);
+                plan.persistContinuations(writer, sourceX, sourceZ, x, z);
+            }
+        });
         transaction.commit();
         logSourcePlanStats();
     }
diff --git a/core/src/main/java/art/arcane/iris/generation/mantle/MantleWriter.java b/core/src/main/java/art/arcane/iris/generation/mantle/MantleWriter.java
index bb94e272f..0a88389d7 100644
--- a/core/src/main/java/art/arcane/iris/generation/mantle/MantleWriter.java
+++ b/core/src/main/java/art/arcane/iris/generation/mantle/MantleWriter.java
@@ -244,7 +244,7 @@ public class MantleWriter implements ObjectPassPlacer, AutoCloseable {
         synchronized (chunk) {
             Matter matter = chunk.getOrCreate(y >> 4);
             if ((t instanceof NativeBlockState || t instanceof MatterCavern)
-                    && (hasProtectedHydrology(matter, x, y, z) || protectsSubterrainPlacement(x, y, z))) {
+                    && hasProtectedHydrology(matter, x, y, z)) {
                 return;
             }
             if (t instanceof NativeBlockState) {
diff --git a/core/src/main/java/art/arcane/iris/generation/mantle/MutationLog.java b/core/src/main/java/art/arcane/iris/generation/mantle/MutationLog.java
new file mode 100644
index 000000000..2480cf184
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/mantle/MutationLog.java
@@ -0,0 +1,89 @@
+package art.arcane.iris.generation.mantle;
+
+import art.arcane.volmlib.nativelib.terrain.NativeBlockState;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Objects;
+
+final class MutationLog {
+    private static final byte CUSTOM = 1;
+    private static final byte CANOPY = 2;
+
+    private int size;
+    private int[] x = new int[32];
+    private int[] y = new int[32];
+    private int[] z = new int[32];
+    private Object[] values = new Object[32];
+    private byte[] flags = new byte[32];
+
+    static MutationLog of(List<ObjectDestinationTransaction.Mutation> mutations) {
+        MutationLog log = new MutationLog();
+        for (ObjectDestinationTransaction.Mutation mutation : mutations) {
+            Objects.requireNonNull(mutation, "mutation");
+            ObjectDestinationTransaction.DataKey key = mutation.key();
+            switch (mutation) {
+                case ObjectDestinationTransaction.SetMutation set -> {
+                    Object value = Objects.requireNonNull(set.value(), "mutation value");
+                    if (ObjectSourcePlan.typeOf(value) != key.type()) {
+                        throw new IllegalArgumentException("Object mutation type " + key.type().getName()
+                                + " does not match its value " + value.getClass().getName());
+                    }
+                    log.add(key.x(), key.y(), key.z(), value, false, set.canopy());
+                }
+                case ObjectDestinationTransaction.CustomBlockMutation block -> log.add(key.x(), key.y(), key.z(),
+                        Objects.requireNonNull(block.state(), "custom block state"), true, block.canopy());
+            }
+        }
+        return log;
+    }
+
+    void add(int blockX, int blockY, int blockZ, Object value, boolean custom, boolean canopy) {
+        if (size == values.length) {
+            int capacity = size * 2;
+            x = Arrays.copyOf(x, capacity);
+            y = Arrays.copyOf(y, capacity);
+            z = Arrays.copyOf(z, capacity);
+            values = Arrays.copyOf(values, capacity);
+            flags = Arrays.copyOf(flags, capacity);
+        }
+        x[size] = blockX;
+        y[size] = blockY;
+        z[size] = blockZ;
+        values[size] = value;
+        flags[size] = (byte) ((custom ? CUSTOM : 0) | (canopy ? CANOPY : 0));
+        size++;
+    }
+
+    int size() {
+        return size;
+    }
+
+    int x(int index) {
+        return x[index];
+    }
+
+    int y(int index) {
+        return y[index];
+    }
+
+    int z(int index) {
+        return z[index];
+    }
+
+    Object value(int index) {
+        return values[index];
+    }
+
+    boolean custom(int index) {
+        return (flags[index] & CUSTOM) != 0;
+    }
+
+    boolean canopy(int index) {
+        return (flags[index] & CANOPY) != 0;
+    }
+
+    Class<?> type(int index) {
+        return custom(index) ? NativeBlockState.class : ObjectSourcePlan.typeOf(values[index]);
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/mantle/ObjectDestinationTransaction.java b/core/src/main/java/art/arcane/iris/generation/mantle/ObjectDestinationTransaction.java
index f1012ec84..546c14200 100644
--- a/core/src/main/java/art/arcane/iris/generation/mantle/ObjectDestinationTransaction.java
+++ b/core/src/main/java/art/arcane/iris/generation/mantle/ObjectDestinationTransaction.java
@@ -8,7 +8,6 @@ import art.arcane.iris.generation.decoration.tree.TreeBlockMaterial;
 import art.arcane.iris.generation.hydrology.cave.HydrologyCaveCell;
 import art.arcane.iris.generation.subterrain.SubterrainRasterizer;
 import art.arcane.iris.generation.block.TileData;
-import art.arcane.iris.structure.object.IObjectPlacer;
 import art.arcane.volmlib.nativelib.terrain.NativeBlockState;
 import art.arcane.volmlib.util.math.BlockPosition;
 import art.arcane.iris.generation.block.B;
@@ -18,10 +17,11 @@ import org.jetbrains.annotations.Nullable;
 import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
 import it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap;
+import it.unimi.dsi.fastutil.longs.LongOpenHashSet;
+import it.unimi.dsi.fastutil.objects.Reference2IntOpenHashMap;
 
 import java.util.ArrayList;
 import java.util.HashMap;
-import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 
@@ -32,7 +32,7 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
     private final int destinationChunkX;
     private final int destinationChunkZ;
     private final int worldHeight;
-    private final List<Mutation> mutations;
+    private final MutationLog log = new MutationLog();
     private final List<PlacementRange> placements = new ArrayList<>();
     private final Long2ObjectOpenHashMap<Int2ObjectOpenHashMap<OverlayCell>> overlay;
     private BlockPosition canopyPosition;
@@ -40,13 +40,17 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
     private int hydrologyGateChunkX;
     private int hydrologyGateChunkZ;
     private boolean hydrologyGateOpen;
+    private boolean subterrainKnown;
+    private int subterrainX;
+    private int subterrainY;
+    private int subterrainZ;
+    private boolean subterrainProtects;
 
     ObjectDestinationTransaction(MantleWriter writer, int destinationChunkX, int destinationChunkZ) {
         this.writer = writer;
         this.destinationChunkX = destinationChunkX;
         this.destinationChunkZ = destinationChunkZ;
         this.worldHeight = writer.getMantle().getWorldHeight();
-        this.mutations = new ArrayList<>();
         this.overlay = new Long2ObjectOpenHashMap<>();
     }
 
@@ -55,11 +59,11 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
     }
 
     int mutationCheckpoint() {
-        return mutations.size();
+        return log.size();
     }
 
     ObjectSourcePlan sourcePlanSince(int checkpoint) {
-        if (checkpoint < 0 || checkpoint > mutations.size()) {
+        if (checkpoint < 0 || checkpoint > log.size()) {
             throw new IllegalArgumentException("Mutation checkpoint is outside the transaction");
         }
         ArrayList<PlacementRange> accepted = new ArrayList<>();
@@ -68,65 +72,91 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
                 accepted.add(new PlacementRange(placement.start() - checkpoint, placement.end() - checkpoint));
             }
         }
-        return new ObjectSourcePlan(mutations.subList(checkpoint, mutations.size()), accepted);
+        return new ObjectSourcePlan(log, checkpoint, accepted);
     }
 
     @Override
     public int beginObjectPlacement() {
-        return mutations.size();
+        return log.size();
     }
 
     @Override
     public void endObjectPlacement(int checkpoint) {
-        if (checkpoint >= 0 && checkpoint < mutations.size()) {
-            placements.add(new PlacementRange(checkpoint, mutations.size()));
+        if (checkpoint >= 0 && checkpoint < log.size()) {
+            placements.add(new PlacementRange(checkpoint, log.size()));
         }
     }
 
     void apply(ObjectSourcePlan plan) {
+        int slot = plan.destinationSlot(destinationChunkX, destinationChunkZ);
+        if (slot < 0) {
+            return;
+        }
+        int baseX = destinationChunkX << 4;
+        int baseZ = destinationChunkZ << 4;
         boolean skipCanopy = false;
-        for (Mutation mutation : plan.mutationsFor(destinationChunkX, destinationChunkZ)) {
-            if (mutation.key().type() == NativeBlockState.class) {
-                NativeBlockState existing = mutation.canopy() ? get(mutation.key().x(), mutation.key().y(), mutation.key().z()) : null;
+        int end = plan.slotEnd(slot);
+        for (int index = plan.slotStart(slot); index < end; index++) {
+            int cell = plan.cellAt(index);
+            int x = baseX | ObjectSourcePlan.cellX(cell);
+            int y = ObjectSourcePlan.cellY(cell);
+            int z = baseZ | ObjectSourcePlan.cellZ(cell);
+            Object value = plan.valueAt(index);
+            boolean custom = ObjectSourcePlan.isCustom(cell);
+            boolean canopy = ObjectSourcePlan.isCanopy(cell);
+            if (custom || value instanceof NativeBlockState) {
+                NativeBlockState existing = canopy ? get(x, y, z) : null;
                 skipCanopy = existing != null && existing.isSolid();
             }
-            if (mutation.canopy() && skipCanopy) {
+            if (canopy && skipCanopy) {
                 continue;
             }
-            switch (mutation) {
-                case SetMutation set -> setData(set.key().x(), set.key().y(), set.key().z(), set.value(), set);
-                case CustomBlockMutation custom -> set(custom.key().x(), custom.key().y(), custom.key().z(), custom.state(), custom);
+            if (custom) {
+                set(x, y, z, (NativeBlockState) value, true, canopy);
+            } else {
+                setData(x, y, z, value, true, canopy);
             }
         }
     }
 
     private void commitFenced() {
-        LinkedHashMap<DataKey, Object> originals = new LinkedHashMap<>();
+        CommitJournal journal = new CommitJournal();
         try {
-            for (Mutation mutation : mutations) {
-                if (!isDestination(mutation.x(), mutation.z())) {
+            for (int position = 0; position < log.size(); position++) {
+                int x = log.x(position);
+                int z = log.z(position);
+                if (!isDestination(x, z)) {
                     continue;
                 }
-                captureOriginal(originals, mutation.key());
-                if (mutation.key().type() == NativeBlockState.class) {
-                    TileWrapper tile = writer.getDataIfPresent(
-                            mutation.key().x(), mutation.key().y(), mutation.key().z(), TileWrapper.class);
-                    if (tile != null) {
-                        originals.putIfAbsent(new DataKey(
-                                mutation.key().x(), mutation.key().y(), mutation.key().z(), TileWrapper.class), tile);
+                int y = log.y(position);
+                Object value = log.value(position);
+                boolean custom = log.custom(position);
+                Class<?> type = log.type(position);
+                if (!journal.captured(x, y, z, type)) {
+                    journal.capture(x, y, z, type, publishedOrCleared(x, y, z, type));
+                }
+                if (type == NativeBlockState.class) {
+                    if (!journal.captured(x, y, z, TileWrapper.class)) {
+                        TileWrapper tile = writer.getDataIfPresent(x, y, z, TileWrapper.class);
+                        if (tile != null) {
+                            journal.capture(x, y, z, TileWrapper.class, tile);
+                        }
                     }
-                    Identifier identifier = writer.getDataIfPresent(
-                            mutation.key().x(), mutation.key().y(), mutation.key().z(), Identifier.class);
-                    if (identifier != null || mutation instanceof CustomBlockMutation) {
-                        originals.putIfAbsent(new DataKey(
-                                mutation.key().x(), mutation.key().y(), mutation.key().z(), Identifier.class),
-                                identifier == null ? CLEARED : identifier);
+                    if (!journal.captured(x, y, z, Identifier.class)) {
+                        Identifier identifier = writer.getDataIfPresent(x, y, z, Identifier.class);
+                        if (identifier != null || custom) {
+                            journal.capture(x, y, z, Identifier.class, identifier == null ? CLEARED : identifier);
+                        }
                     }
                 }
-                mutation.apply(writer);
+                if (custom) {
+                    writer.set(x, y, z, (NativeBlockState) value);
+                } else {
+                    writer.setData(x, y, z, value);
+                }
             }
         } catch (Throwable failure) {
-            rollback(originals, failure);
+            journal.rollback(failure);
             if (failure instanceof RuntimeException runtimeException) {
                 throw runtimeException;
             }
@@ -149,10 +179,10 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
 
     @Override
     public void set(int x, int y, int z, NativeBlockState state) {
-        set(x, y, z, state, null);
+        set(x, y, z, state, false, false);
     }
 
-    private void set(int x, int y, int z, NativeBlockState state, CustomBlockMutation replayed) {
+    private void set(int x, int y, int z, NativeBlockState state, boolean replayed, boolean replayedCanopy) {
         if (state == null) {
             return;
         }
@@ -167,8 +197,7 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
             cell.block = baseState;
             cell.tile = CLEARED;
             cell.identifier = identifier;
-            mutations.add(replayed != null
-                    ? replayed : new CustomBlockMutation(new DataKey(x, y, z, NativeBlockState.class), state, isCanopy(x, y, z)));
+            log.add(x, y, z, state, true, replayed ? replayedCanopy : isCanopy(x, y, z));
             return;
         }
         setData(x, y, z, state);
@@ -262,10 +291,10 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
 
     @Override
     public <T> void setData(int x, int y, int z, T data) {
-        setData(x, y, z, data, null);
+        setData(x, y, z, data, false, false);
     }
 
-    private void setData(int x, int y, int z, Object data, SetMutation replayed) {
+    private void setData(int x, int y, int z, Object data, boolean replayed, boolean replayedCanopy) {
         if (data == null || y < 0 || y >= worldHeight
                 || protectsSubterrain(x, y, z)) {
             return;
@@ -285,8 +314,7 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
         } else {
             cell.put(type, data);
         }
-        mutations.add(replayed != null
-                ? replayed : new SetMutation(new DataKey(x, y, z, type), data, isCanopy(x, y, z)));
+        log.add(x, y, z, data, false, replayed ? replayedCanopy : isCanopy(x, y, z));
     }
 
     @Override
@@ -368,18 +396,6 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
         return value == null ? CLEARED : value;
     }
 
-    private void captureOriginal(LinkedHashMap<DataKey, Object> originals, DataKey key) {
-        originals.computeIfAbsent(
-                key,
-                candidate -> publishedOrCleared(
-                        candidate.x(),
-                        candidate.y(),
-                        candidate.z(),
-                        candidate.type()
-                )
-        );
-    }
-
     private boolean isDestination(int x, int z) {
         return (x >> 4) == destinationChunkX && (z >> 4) == destinationChunkZ;
     }
@@ -396,8 +412,17 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
     }
 
     private boolean protectsSubterrain(int x, int y, int z) {
+        if (subterrainKnown && x == subterrainX && y == subterrainY && z == subterrainZ) {
+            return subterrainProtects;
+        }
         Engine engine = getEngine();
-        return engine != null && SubterrainRasterizer.protectsPlacement(engine.getSubterrainCell(x, y, z));
+        boolean protects = engine != null && SubterrainRasterizer.protectsPlacement(engine.getSubterrainCell(x, y, z));
+        subterrainX = x;
+        subterrainY = y;
+        subterrainZ = z;
+        subterrainProtects = protects;
+        subterrainKnown = true;
+        return protects;
     }
 
     private boolean hasProtectedHydrology(int x, int y, int z) {
@@ -419,22 +444,44 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
         return hydrologyGateOpen;
     }
 
-    private void rollback(LinkedHashMap<DataKey, Object> originals, Throwable failure) {
-        ArrayList<Map.Entry<DataKey, Object>> entries = new ArrayList<>(originals.entrySet());
-        for (int index = entries.size() - 1; index >= 0; index--) {
-            Map.Entry<DataKey, Object> entry = entries.get(index);
-            DataKey key = entry.getKey();
-            try {
-                writer.restoreData(key.x(), key.y(), key.z(), key.type(),
-                        entry.getValue() == CLEARED ? null : entry.getValue());
-            } catch (Throwable rollbackFailure) {
-                if (rollbackFailure != failure) {
-                    failure.addSuppressed(rollbackFailure);
+    private final class CommitJournal {
+        private final Reference2IntOpenHashMap<Class<?>> typeIds = new Reference2IntOpenHashMap<>();
+        private final LongOpenHashSet keys = new LongOpenHashSet();
+        private final ArrayList<Original> originals = new ArrayList<>();
+
+        private long key(int x, int y, int z, Class<?> type) {
+            int typeId = typeIds.computeIfAbsent(type, (Class<?> ignored) -> typeIds.size());
+            return ((long) typeId << 32) | ((long) y << 8) | ((long) (z & 15) << 4) | (x & 15);
+        }
+
+        private boolean captured(int x, int y, int z, Class<?> type) {
+            return keys.contains(key(x, y, z, type));
+        }
+
+        private void capture(int x, int y, int z, Class<?> type, Object value) {
+            if (keys.add(key(x, y, z, type))) {
+                originals.add(new Original(x, y, z, type, value));
+            }
+        }
+
+        private void rollback(Throwable failure) {
+            for (int index = originals.size() - 1; index >= 0; index--) {
+                Original original = originals.get(index);
+                try {
+                    writer.restoreData(original.x(), original.y(), original.z(), original.type(),
+                            original.value() == CLEARED ? null : original.value());
+                } catch (Throwable rollbackFailure) {
+                    if (rollbackFailure != failure) {
+                        failure.addSuppressed(rollbackFailure);
+                    }
                 }
             }
         }
     }
 
+    private record Original(int x, int y, int z, Class<?> type, Object value) {
+    }
+
     private static final class OverlayCell {
         private Object block;
         private Object hydrology;
@@ -506,8 +553,6 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
         DataKey key();
 
         boolean canopy();
-
-        void apply(IObjectPlacer placer);
     }
 
     record SetMutation(DataKey key, Object value, boolean canopy) implements Mutation {
@@ -520,11 +565,6 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
         public int z() {
             return key.z();
         }
-
-        @Override
-        public void apply(IObjectPlacer placer) {
-            placer.setData(key.x(), key.y(), key.z(), value);
-        }
     }
 
     record CustomBlockMutation(DataKey key, NativeBlockState state, boolean canopy) implements Mutation {
@@ -537,10 +577,5 @@ final class ObjectDestinationTransaction implements ObjectPassPlacer {
         public int z() {
             return key.z();
         }
-
-        @Override
-        public void apply(IObjectPlacer placer) {
-            placer.set(key.x(), key.y(), key.z(), state);
-        }
     }
 }
diff --git a/core/src/main/java/art/arcane/iris/generation/mantle/ObjectSourcePlan.java b/core/src/main/java/art/arcane/iris/generation/mantle/ObjectSourcePlan.java
index 236c1b90c..ab7e12def 100644
--- a/core/src/main/java/art/arcane/iris/generation/mantle/ObjectSourcePlan.java
+++ b/core/src/main/java/art/arcane/iris/generation/mantle/ObjectSourcePlan.java
@@ -20,7 +20,6 @@ import it.unimi.dsi.fastutil.objects.Reference2IntOpenHashMap;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
-import java.util.Objects;
 
 final class ObjectSourcePlan {
     static final ObjectSourcePlan EMPTY = new ObjectSourcePlan(List.of());
@@ -45,18 +44,21 @@ final class ObjectSourcePlan {
     private final int estimatedRetainedBytes;
 
     ObjectSourcePlan(List<ObjectDestinationTransaction.Mutation> mutations) {
-        this(mutations, List.of());
+        this(MutationLog.of(mutations), 0, List.of());
     }
 
     ObjectSourcePlan(List<ObjectDestinationTransaction.Mutation> mutations, List<ObjectDestinationTransaction.PlacementRange> accepted) {
-        int count = mutations.size();
+        this(MutationLog.of(mutations), 0, accepted);
+    }
+
+    ObjectSourcePlan(MutationLog log, int from, List<ObjectDestinationTransaction.PlacementRange> accepted) {
+        int count = log.size() - from;
         long[] mutationDestinations = new long[count];
         Long2IntOpenHashMap destinationSlots = new Long2IntOpenHashMap();
         destinationSlots.defaultReturnValue(-1);
         LongArrayList firstSeen = new LongArrayList();
         for (int index = 0; index < count; index++) {
-            ObjectDestinationTransaction.Mutation mutation = Objects.requireNonNull(mutations.get(index), "mutation");
-            long destination = destinationKey(mutation.x() >> 4, mutation.z() >> 4);
+            long destination = destinationKey(log.x(from + index) >> 4, log.z(from + index) >> 4);
             mutationDestinations[index] = destination;
             if (destinationSlots.putIfAbsent(destination, firstSeen.size()) == -1) {
                 firstSeen.add(destination);
@@ -80,38 +82,23 @@ final class ObjectSourcePlan {
         valueIndexes = new int[count];
         ValueTable table = new ValueTable();
         for (int index = 0; index < count; index++) {
-            ObjectDestinationTransaction.Mutation mutation = mutations.get(index);
+            int logged = from + index;
             int position = cursor[destinationSlots.get(mutationDestinations[index])]++;
             positions[index] = position;
-            ObjectDestinationTransaction.DataKey key = mutation.key();
-            if (key.y() < 0 || key.y() > MAXIMUM_Y) {
-                throw new IllegalArgumentException("Object mutation height is outside the plan range: " + key.y());
+            int y = log.y(logged);
+            if (y < 0 || y > MAXIMUM_Y) {
+                throw new IllegalArgumentException("Object mutation height is outside the plan range: " + y);
             }
-            Object value;
-            int custom;
-            switch (mutation) {
-                case ObjectDestinationTransaction.SetMutation set -> {
-                    value = Objects.requireNonNull(set.value(), "mutation value");
-                    if (typeOf(value) != key.type()) {
-                        throw new IllegalArgumentException("Object mutation type " + key.type().getName()
-                                + " does not match its value " + value.getClass().getName());
-                    }
-                    custom = 0;
-                }
-                case ObjectDestinationTransaction.CustomBlockMutation block -> {
-                    value = Objects.requireNonNull(block.state(), "custom block state");
-                    custom = CUSTOM_BIT;
-                }
-            }
-            cells[position] = (key.y() << Y_SHIFT) | custom | (mutation.canopy() ? CANOPY_BIT : 0) | ((key.z() & 15) << 4) | (key.x() & 15);
-            valueIndexes[position] = table.indexOf(value);
+            cells[position] = (y << Y_SHIFT) | (log.custom(logged) ? CUSTOM_BIT : 0) | (log.canopy(logged) ? CANOPY_BIT : 0)
+                    | ((log.z(logged) & 15) << 4) | (log.x(logged) & 15);
+            valueIndexes[position] = table.indexOf(log.value(logged));
         }
         values = table.values.toArray();
 
         ArrayList<Placement> crossing = new ArrayList<>();
         for (int ordinal = 0; ordinal < accepted.size(); ordinal++) {
             ObjectDestinationTransaction.PlacementRange range = accepted.get(ordinal);
-            Placement placement = crossingPlacement(ordinal, range.start(), range.end(), mutations, mutationDestinations, destinationSlots, positions);
+            Placement placement = crossingPlacement(ordinal, range.start(), range.end(), log, from, mutationDestinations, destinationSlots, positions);
             if (placement != null) {
                 crossing.add(placement);
             }
@@ -147,12 +134,13 @@ final class ObjectSourcePlan {
             int ordinal,
             int start,
             int end,
-            List<ObjectDestinationTransaction.Mutation> mutations,
+            MutationLog log,
+            int from,
             long[] mutationDestinations,
             Long2IntOpenHashMap destinationSlots,
             int[] positions
     ) {
-        if (start < 0 || end > mutations.size() || start >= end) {
+        if (start < 0 || end > log.size() - from || start >= end) {
             throw new IllegalArgumentException("Object placement range is outside the plan");
         }
         long first = mutationDestinations[start];
@@ -172,11 +160,12 @@ final class ObjectSourcePlan {
         int maximumX = Integer.MIN_VALUE;
         int maximumZ = Integer.MIN_VALUE;
         for (int mutationIndex = start; mutationIndex < end; mutationIndex++) {
-            ObjectDestinationTransaction.Mutation mutation = mutations.get(mutationIndex);
-            minimumX = Math.min(minimumX, mutation.x());
-            minimumZ = Math.min(minimumZ, mutation.z());
-            maximumX = Math.max(maximumX, mutation.x());
-            maximumZ = Math.max(maximumZ, mutation.z());
+            int mutationX = log.x(from + mutationIndex);
+            int mutationZ = log.z(from + mutationIndex);
+            minimumX = Math.min(minimumX, mutationX);
+            minimumZ = Math.min(minimumZ, mutationZ);
+            maximumX = Math.max(maximumX, mutationX);
+            maximumZ = Math.max(maximumZ, mutationZ);
             long destination = mutationDestinations[mutationIndex];
             int touchedIndex = touchedIndexes.get(destination);
             if (touchedIndex < 0) {
@@ -216,6 +205,55 @@ final class ObjectSourcePlan {
         return destinations.length == 0;
     }
 
+    int slotStart(int slot) {
+        return offsets[slot];
+    }
+
+    int slotEnd(int slot) {
+        return offsets[slot + 1];
+    }
+
+    int cellAt(int index) {
+        return cells[index];
+    }
+
+    Object valueAt(int index) {
+        return values[valueIndexes[index]];
+    }
+
+    static int cellX(int cell) {
+        return cell & 15;
+    }
+
+    static int cellZ(int cell) {
+        return (cell >>> 4) & 15;
+    }
+
+    static int cellY(int cell) {
+        return cell >>> Y_SHIFT;
+    }
+
+    static boolean isCustom(int cell) {
+        return (cell & CUSTOM_BIT) != 0;
+    }
+
+    static boolean isCanopy(int cell) {
+        return (cell & CANOPY_BIT) != 0;
+    }
+
+    ObjectDestinationTransaction.Mutation mutationAt(int chunkX, int chunkZ, int index) {
+        int cell = cells[index];
+        int x = (chunkX << 4) | cellX(cell);
+        int z = (chunkZ << 4) | cellZ(cell);
+        int y = cellY(cell);
+        Object value = valueAt(index);
+        return isCustom(cell)
+                ? new ObjectDestinationTransaction.CustomBlockMutation(
+                new ObjectDestinationTransaction.DataKey(x, y, z, NativeBlockState.class), (NativeBlockState) value, isCanopy(cell))
+                : new ObjectDestinationTransaction.SetMutation(
+                new ObjectDestinationTransaction.DataKey(x, y, z, typeOf(value)), value, isCanopy(cell));
+    }
+
     List<ObjectDestinationTransaction.Mutation> mutationsFor(int chunkX, int chunkZ) {
         int slot = destinationSlot(chunkX, chunkZ);
         return slot < 0 ? List.of() : decode(chunkX, chunkZ, offsets[slot], offsets[slot + 1] - offsets[slot]);
@@ -266,19 +304,8 @@ final class ObjectSourcePlan {
 
     private List<ObjectDestinationTransaction.Mutation> decode(int chunkX, int chunkZ, int start, int length) {
         ObjectDestinationTransaction.Mutation[] decoded = new ObjectDestinationTransaction.Mutation[length];
-        int baseX = chunkX << 4;
-        int baseZ = chunkZ << 4;
         for (int index = 0; index < length; index++) {
-            int cell = cells[start + index];
-            int x = baseX | (cell & 15);
-            int z = baseZ | ((cell >>> 4) & 15);
-            int y = cell >>> Y_SHIFT;
-            Object value = values[valueIndexes[start + index]];
-            decoded[index] = (cell & CUSTOM_BIT) != 0
-                    ? new ObjectDestinationTransaction.CustomBlockMutation(
-                    new ObjectDestinationTransaction.DataKey(x, y, z, NativeBlockState.class), (NativeBlockState) value, (cell & CANOPY_BIT) != 0)
-                    : new ObjectDestinationTransaction.SetMutation(
-                    new ObjectDestinationTransaction.DataKey(x, y, z, typeOf(value)), value, (cell & CANOPY_BIT) != 0);
+            decoded[index] = mutationAt(chunkX, chunkZ, start + index);
         }
         return List.of(decoded);
     }
diff --git a/core/src/main/java/art/arcane/iris/generation/mantle/ObjectSourcePlanCache.java b/core/src/main/java/art/arcane/iris/generation/mantle/ObjectSourcePlanCache.java
index 4b73e6dce..daa1a1580 100644
--- a/core/src/main/java/art/arcane/iris/generation/mantle/ObjectSourcePlanCache.java
+++ b/core/src/main/java/art/arcane/iris/generation/mantle/ObjectSourcePlanCache.java
@@ -4,6 +4,7 @@ import com.github.benmanes.caffeine.cache.Cache;
 import com.github.benmanes.caffeine.cache.Caffeine;
 import art.arcane.volmlib.util.cache.CacheKey;
 
+import java.util.List;
 import java.util.Objects;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.CompletionException;
@@ -14,6 +15,7 @@ import java.util.function.Supplier;
 import static art.arcane.iris.generation.cache.Cache.key;
 
 final class ObjectSourcePlanCache {
+    static final ObjectSourcePlan BUSY = new ObjectSourcePlan(List.of());
     private static final long MAXIMUM_RETAINED_BYTES = 512L * 1024L * 1024L;
     private static final int ENTRY_BYTES = 64;
 
@@ -68,6 +70,19 @@ final class ObjectSourcePlanCache {
         return plan;
     }
 
+    ObjectSourcePlan tryAcquire(int sourceChunkX, int sourceChunkZ, int destinationChunkX, int destinationChunkZ,
+                                int sourceChunkRadius, Supplier<ObjectSourcePlan> builder) {
+        State current = state;
+        long source = CacheKey.mix(key(sourceChunkX, sourceChunkZ));
+        if (current.plans.getIfPresent(source) == null) {
+            Pending pending = current.pending.get(source);
+            if (pending != null && pending.owner != Thread.currentThread()) {
+                return BUSY;
+            }
+        }
+        return acquire(sourceChunkX, sourceChunkZ, destinationChunkX, destinationChunkZ, sourceChunkRadius, builder);
+    }
+
     private ObjectSourcePlan claim(State current, long source, Entry entry, int destinationChunkX, int destinationChunkZ,
                                    Supplier<ObjectSourcePlan> builder) {
         int slot = entry.slot(destinationChunkX, destinationChunkZ);
diff --git a/core/src/main/java/art/arcane/iris/generation/noise/GeneratorProgram.java b/core/src/main/java/art/arcane/iris/generation/noise/GeneratorProgram.java
new file mode 100644
index 000000000..360746480
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/noise/GeneratorProgram.java
@@ -0,0 +1,289 @@
+package art.arcane.iris.generation.noise;
+
+import art.arcane.volmlib.util.interpolation.IrisInterpolation;
+
+import java.util.Arrays;
+
+public final class GeneratorProgram {
+    private static final int SURFACE_GRID = 6;
+
+    private final IrisGenerator generator;
+    private final long superSeed;
+    private final NoiseLayerProgram[] layers;
+    private final double totalOpacity;
+    private final NoiseLayerProgram cliffs;
+    private final boolean multiplicitive;
+    private final double opacity;
+    private final double offsetX;
+    private final double offsetZ;
+    private final double zoom;
+    private final double surfaceDetail;
+    private final double cliffHeightMin;
+    private final double cliffHeightMax;
+    private final boolean cellCracks;
+
+    GeneratorProgram(IrisGenerator generator, long superSeed, NoiseLayerProgram[] layers, double totalOpacity, NoiseLayerProgram cliffs) {
+        this.generator = generator;
+        this.superSeed = superSeed;
+        this.layers = layers;
+        this.totalOpacity = totalOpacity;
+        this.cliffs = cliffs;
+        this.multiplicitive = generator.isMultiplicitive();
+        this.opacity = generator.getOpacity();
+        this.offsetX = generator.getOffsetX();
+        this.offsetZ = generator.getOffsetZ();
+        this.zoom = generator.getZoom();
+        this.surfaceDetail = generator.getSurfaceDetail();
+        this.cliffHeightMin = generator.getCliffHeightMin();
+        this.cliffHeightMax = generator.getCliffHeightMax();
+        this.cellCracks = generator.getCellFractureHeight() != 0;
+    }
+
+    public IrisGenerator generator() {
+        return generator;
+    }
+
+    public void heights(TerrainBatchScratch scratch, double[] xs, double[] zs, int count, double[] out) {
+        if (count == 0) {
+            return;
+        }
+        if (layers.length == 0) {
+            Arrays.fill(out, 0, count, 0D);
+            return;
+        }
+        if (surfaceDetail == 1D) {
+            sample(scratch, xs, zs, count, out);
+            return;
+        }
+        surfaceHeights(scratch, xs, zs, count, out);
+    }
+
+    public double height(TerrainBatchScratch scratch, double x, double z) {
+        if (layers.length == 0) {
+            return 0D;
+        }
+        if (surfaceDetail == 1D) {
+            return sample(scratch, x, z);
+        }
+        double lowerX = Math.floor(x / SURFACE_GRID) * SURFACE_GRID;
+        double lowerZ = Math.floor(z / SURFACE_GRID) * SURFACE_GRID;
+        double dx = (x - lowerX) / SURFACE_GRID;
+        double dz = (z - lowerZ) / SURFACE_GRID;
+        IrisGenerator.SurfaceCacheStripe[] stripes = generator.surfaceStripes();
+        double northWest = lattice(scratch, stripes, lowerX, lowerZ);
+        if (dx == 0D && dz == 0D) {
+            return northWest;
+        }
+        double north = dx == 0D ? northWest
+                : IrisInterpolation.lerp(northWest, lattice(scratch, stripes, lowerX + SURFACE_GRID, lowerZ), dx);
+        double smooth = north;
+        if (dz != 0D) {
+            double southWest = lattice(scratch, stripes, lowerX, lowerZ + SURFACE_GRID);
+            double south = dx == 0D ? southWest
+                    : IrisInterpolation.lerp(southWest, lattice(scratch, stripes, lowerX + SURFACE_GRID, lowerZ + SURFACE_GRID), dx);
+            smooth = IrisInterpolation.lerp(north, south, dz);
+        }
+        return surfaceDetail == 0D ? smooth : smooth + (sample(scratch, x, z) - smooth) * surfaceDetail;
+    }
+
+    private double lattice(TerrainBatchScratch scratch, IrisGenerator.SurfaceCacheStripe[] stripes, double x, double z) {
+        if (x != (int) x || z != (int) z) {
+            return sample(scratch, x, z);
+        }
+        int mark = scratch.mark();
+        double[] cached = scratch.buffer(1);
+        boolean hit = IrisGenerator.cachedSurface(stripes, x, z, superSeed, cached, 0);
+        double value = cached[0];
+        scratch.reset(mark);
+        if (hit) {
+            return value;
+        }
+        double height = sample(scratch, x, z);
+        IrisGenerator.storeSurface(stripes, x, z, superSeed, height);
+        return height;
+    }
+
+    private double sample(TerrainBatchScratch scratch, double x, double z) {
+        double sampleX = (x + offsetX) / zoom;
+        double sampleZ = (z + offsetZ) / zoom;
+        double value = multiplicitive ? 1D : 0D;
+        for (NoiseLayerProgram layer : layers) {
+            double noise = layer.sample(scratch, sampleX, sampleZ);
+            value = multiplicitive ? value * noise : value + noise;
+        }
+        value = multiplicitive ? value * opacity : (value / totalOpacity) * opacity;
+        if (Double.isNaN(value)) {
+            value = 0D;
+        }
+        if (cliffs != null) {
+            double height = IrisInterpolation.lerp(cliffHeightMin, cliffHeightMax, cliffs.sample(scratch, sampleX, sampleZ));
+            value = (Math.round((value * 255D) / height) * height) / 255D;
+        }
+        return cellCracks ? generator.cell(x, z, value, 0D) : value;
+    }
+
+    private void surfaceHeights(TerrainBatchScratch scratch, double[] xs, double[] zs, int count, double[] out) {
+        int mark = scratch.mark();
+        int indexMark = scratch.indexMark();
+        int[] northWest = scratch.indices(count);
+        int[] northEast = scratch.indices(count);
+        int[] southWest = scratch.indices(count);
+        int[] southEast = scratch.indices(count);
+        double[] fractionX = scratch.buffer(count);
+        double[] fractionZ = scratch.buffer(count);
+        scratch.clearLattice(count * 4);
+        int detailed = 0;
+        double previousX = Double.NaN;
+        double previousZ = Double.NaN;
+        int cellNorthWest = -1;
+        int cellNorthEast = -1;
+        int cellSouthWest = -1;
+        int cellSouthEast = -1;
+        for (int index = 0; index < count; index++) {
+            double lowerX = Math.floor(xs[index] / SURFACE_GRID) * SURFACE_GRID;
+            double lowerZ = Math.floor(zs[index] / SURFACE_GRID) * SURFACE_GRID;
+            double dx = (xs[index] - lowerX) / SURFACE_GRID;
+            double dz = (zs[index] - lowerZ) / SURFACE_GRID;
+            fractionX[index] = dx;
+            fractionZ[index] = dz;
+            if (Double.doubleToRawLongBits(lowerX) != Double.doubleToRawLongBits(previousX)
+                    || Double.doubleToRawLongBits(lowerZ) != Double.doubleToRawLongBits(previousZ)) {
+                previousX = lowerX;
+                previousZ = lowerZ;
+                cellNorthWest = scratch.lattice(lowerX, lowerZ);
+                cellNorthEast = -1;
+                cellSouthWest = -1;
+                cellSouthEast = -1;
+            }
+            if (dx != 0D && cellNorthEast < 0) {
+                cellNorthEast = scratch.lattice(lowerX + SURFACE_GRID, lowerZ);
+            }
+            if (dz != 0D && cellSouthWest < 0) {
+                cellSouthWest = scratch.lattice(lowerX, lowerZ + SURFACE_GRID);
+            }
+            if (dx != 0D && dz != 0D && cellSouthEast < 0) {
+                cellSouthEast = scratch.lattice(lowerX + SURFACE_GRID, lowerZ + SURFACE_GRID);
+            }
+            northWest[index] = cellNorthWest;
+            northEast[index] = dx == 0D ? -1 : cellNorthEast;
+            southWest[index] = dz == 0D ? -1 : cellSouthWest;
+            southEast[index] = dx == 0D || dz == 0D ? -1 : cellSouthEast;
+            if (dx != 0D || dz != 0D) {
+                detailed++;
+            }
+        }
+        int nodes = scratch.latticeCount();
+        double[] lattice = scratch.buffer(nodes);
+        resolveLattice(scratch, nodes, lattice);
+        double[] detail = null;
+        int[] detailIndex = null;
+        if (surfaceDetail != 0D && detailed > 0) {
+            double[] detailX = scratch.buffer(detailed);
+            double[] detailZ = scratch.buffer(detailed);
+            detail = scratch.buffer(detailed);
+            detailIndex = scratch.indices(count);
+            int cursor = 0;
+            for (int index = 0; index < count; index++) {
+                if (fractionX[index] != 0D || fractionZ[index] != 0D) {
+                    detailX[cursor] = xs[index];
+                    detailZ[cursor] = zs[index];
+                    detailIndex[index] = cursor++;
+                }
+            }
+            sample(scratch, detailX, detailZ, detailed, detail);
+        }
+        for (int index = 0; index < count; index++) {
+            double dx = fractionX[index];
+            double dz = fractionZ[index];
+            double nw = lattice[northWest[index]];
+            if (dx == 0D && dz == 0D) {
+                out[index] = nw;
+                continue;
+            }
+            double north = dx == 0D ? nw : IrisInterpolation.lerp(nw, lattice[northEast[index]], dx);
+            double smooth = north;
+            if (dz != 0D) {
+                double sw = lattice[southWest[index]];
+                double south = dx == 0D ? sw : IrisInterpolation.lerp(sw, lattice[southEast[index]], dx);
+                smooth = IrisInterpolation.lerp(north, south, dz);
+            }
+            out[index] = surfaceDetail == 0D ? smooth : smooth + (detail[detailIndex[index]] - smooth) * surfaceDetail;
+        }
+        scratch.resetIndices(indexMark);
+        scratch.reset(mark);
+    }
+
+    private void resolveLattice(TerrainBatchScratch scratch, int nodes, double[] lattice) {
+        IrisGenerator.SurfaceCacheStripe[] stripes = generator.surfaceStripes();
+        int indexMark = scratch.indexMark();
+        int mark = scratch.mark();
+        int[] missing = scratch.indices(nodes);
+        double[] missingX = scratch.buffer(nodes);
+        double[] missingZ = scratch.buffer(nodes);
+        int missingCount = 0;
+        for (int node = 0; node < nodes; node++) {
+            double x = scratch.latticeX(node);
+            double z = scratch.latticeZ(node);
+            if (x == (int) x && z == (int) z && IrisGenerator.cachedSurface(stripes, x, z, superSeed, lattice, node)) {
+                continue;
+            }
+            missing[missingCount] = node;
+            missingX[missingCount] = x;
+            missingZ[missingCount++] = z;
+        }
+        if (missingCount > 0) {
+            double[] sampled = scratch.buffer(missingCount);
+            sample(scratch, missingX, missingZ, missingCount, sampled);
+            for (int index = 0; index < missingCount; index++) {
+                int node = missing[index];
+                lattice[node] = sampled[index];
+                if (missingX[index] == (int) missingX[index] && missingZ[index] == (int) missingZ[index]) {
+                    IrisGenerator.storeSurface(stripes, missingX[index], missingZ[index], superSeed, sampled[index]);
+                }
+            }
+        }
+        scratch.reset(mark);
+        scratch.resetIndices(indexMark);
+    }
+
+    private void sample(TerrainBatchScratch scratch, double[] xs, double[] zs, int count, double[] out) {
+        int mark = scratch.mark();
+        double[] sampleX = scratch.buffer(count);
+        double[] sampleZ = scratch.buffer(count);
+        double[] noise = scratch.buffer(count);
+        for (int index = 0; index < count; index++) {
+            sampleX[index] = (xs[index] + offsetX) / zoom;
+            sampleZ[index] = (zs[index] + offsetZ) / zoom;
+        }
+        Arrays.fill(out, 0, count, multiplicitive ? 1D : 0D);
+        for (NoiseLayerProgram layer : layers) {
+            layer.evaluate(scratch, sampleX, sampleZ, count, noise);
+            if (multiplicitive) {
+                for (int index = 0; index < count; index++) {
+                    out[index] *= noise[index];
+                }
+            } else {
+                for (int index = 0; index < count; index++) {
+                    out[index] += noise[index];
+                }
+            }
+        }
+        for (int index = 0; index < count; index++) {
+            double value = multiplicitive ? out[index] * opacity : (out[index] / totalOpacity) * opacity;
+            out[index] = Double.isNaN(value) ? 0D : value;
+        }
+        if (cliffs != null) {
+            cliffs.evaluate(scratch, sampleX, sampleZ, count, noise);
+            for (int index = 0; index < count; index++) {
+                double height = IrisInterpolation.lerp(cliffHeightMin, cliffHeightMax, noise[index]);
+                out[index] = (Math.round((out[index] * 255D) / height) * height) / 255D;
+            }
+        }
+        if (cellCracks) {
+            for (int index = 0; index < count; index++) {
+                out[index] = generator.cell(xs[index], zs[index], out[index], 0D);
+            }
+        }
+        scratch.reset(mark);
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/noise/IrisGenerator.java b/core/src/main/java/art/arcane/iris/generation/noise/IrisGenerator.java
index 6ff6032fb..dd5ebd912 100644
--- a/core/src/main/java/art/arcane/iris/generation/noise/IrisGenerator.java
+++ b/core/src/main/java/art/arcane/iris/generation/noise/IrisGenerator.java
@@ -41,10 +41,7 @@ import lombok.Getter;
 import lombok.Setter;
 import lombok.experimental.Accessors;
 
-import java.util.Arrays;
 import java.util.List;
-import java.util.Objects;
-import java.util.function.DoubleBinaryOperator;
 
 @Accessors(chain = true)
 @NoArgsConstructor
@@ -211,7 +208,7 @@ public class IrisGenerator extends IrisRegistrant {
         if (surfaceDetail == 1D) {
             return sampleHeight(rx, rz, superSeed, data, engine);
         }
-        return surfaceHeight(rx, rz, superSeed, data, engine, null);
+        return surfaceHeight(rx, rz, superSeed, data, engine);
     }
 
     public boolean supportsBatch() {
@@ -227,90 +224,84 @@ public class IrisGenerator extends IrisRegistrant {
         return !hasCliffs() || cliffHeightGenerator.supportsBatch();
     }
 
-    public void getHeights(double[] xs, double[] zs, long superSeed, double[] target, int count) {
-        Objects.checkFromIndexSize(0, count, xs.length);
-        Objects.checkFromIndexSize(0, count, zs.length);
-        Objects.checkFromIndexSize(0, count, target.length);
-        if (count > 4096) {
-            throw new IllegalArgumentException("Generator batch exceeds 4096 samples");
+    public GeneratorProgram compileProgram(long superSeed) {
+        if (!Double.isFinite(surfaceDetail) || surfaceDetail < 0D || surfaceDetail > 1D) {
+            throw new IllegalArgumentException("Generator surfaceDetail must be finite and between 0 and 1");
         }
-        if (count < 8 || !supportsBatch()) {
-            for (int index = 0; index < count; index++) {
-                target[index] = getHeight(xs[index], zs[index], superSeed);
-            }
-            return;
-        }
-        if (composite.isEmpty()) {
-            Arrays.fill(target, 0, count, 0D);
-            return;
+        if (!supportsBatch()) {
+            throw new IllegalStateException("Generator " + getLoadKey() + " cannot be compiled into a batch program");
         }
         IrisData data = getLoader();
         Engine engine = data == null ? null : data.getEngine();
-        DoubleBinaryOperator prepared = prepareHeight(superSeed, data, engine);
-        for (int index = 0; index < count; index++) {
-            target[index] = surfaceDetail == 1D ? prepared.applyAsDouble(xs[index], zs[index])
-                    : surfaceHeight(xs[index], zs[index], superSeed, data, engine, prepared);
-        }
-    }
-
-    private DoubleBinaryOperator prepareHeight(long superSeed, IrisData data, Engine engine) {
         int hc = (int) ((cliffHeightMin * 10) + 10 + cliffHeightMax * getSeed() + offsetX + offsetZ);
-        DoubleBinaryOperator[] layers = new DoubleBinaryOperator[composite.size()];
+        NoiseLayerProgram[] layers = new NoiseLayerProgram[composite.size()];
         double totalOpacity = 0D;
         for (int index = 0; index < layers.length; index++) {
             IrisNoiseGenerator layer = composite.get(index);
-            layers[index] = layer.prepareBatch(getSeed() + superSeed + hc, data, engine);
+            layers[index] = layer.compileProgram(getSeed() + superSeed + hc, data, engine);
             if (!multiplicitive) {
                 totalOpacity += layer.getOpacity();
             }
         }
-        double sumOpacity = totalOpacity;
         double cliffSeed = (double) (superSeed + 294596 + hc) - 34857;
-        DoubleBinaryOperator cliffs = hasCliffs() ? cliffHeightGenerator.prepareBatch(
-                (long) (getSeed() + cliffSeed + hc), data, engine) : null;
-        return (rx, rz) -> {
-            double sampleX = (rx + offsetX) / zoom;
-            double sampleZ = (rz + offsetZ) / zoom;
-            double h = multiplicitive ? 1D : 0D;
-            for (DoubleBinaryOperator layer : layers) {
-                double sampled = layer.applyAsDouble(sampleX, sampleZ);
-                h = multiplicitive ? h * sampled : h + sampled;
-            }
-            double value = multiplicitive ? h * opacity : (h / sumOpacity) * opacity;
-            if (Double.isNaN(value)) {
-                value = 0D;
-            }
-            if (cliffs != null) {
-                double height = IrisInterpolation.lerp(cliffHeightMin, cliffHeightMax,
-                        cliffs.applyAsDouble(sampleX, sampleZ));
-                value = (Math.round((value * 255D) / height) * height) / 255D;
-            }
-            return hasCellCracks() ? cell(rx, rz, value, superSeed + 48622 + hc) : value;
-        };
+        NoiseLayerProgram cliffs = hasCliffs()
+                ? cliffHeightGenerator.compileProgram((long) (getSeed() + cliffSeed + hc), data, engine)
+                : null;
+        return new GeneratorProgram(this, superSeed, layers, totalOpacity, cliffs);
     }
 
-    private double surfaceHeight(double rx, double rz, long superSeed, IrisData data, Engine engine,
-                                 DoubleBinaryOperator prepared) {
+    SurfaceCacheStripe[] surfaceStripes() {
+        IrisData data = getLoader();
+        return surfaceCache(data, data == null ? null : data.getEngine()).stripes();
+    }
+
+    static boolean cachedSurface(SurfaceCacheStripe[] stripes, double x, double z, long superSeed, double[] target, int index) {
+        long key = ((long) (int) x << 32) | ((int) z & 0xffffffffL);
+        long mixed = surfaceMix(key);
+        SurfaceSample cached = stripes[(int) mixed & (SURFACE_CACHE_STRIPES - 1)]
+                .get(key, superSeed, (int) (mixed >>> 4) & (SURFACE_CACHE_STRIPE_SIZE - 1));
+        if (cached == null) {
+            return false;
+        }
+        target[index] = cached.height();
+        return true;
+    }
+
+    static void storeSurface(SurfaceCacheStripe[] stripes, double x, double z, long superSeed, double height) {
+        long key = ((long) (int) x << 32) | ((int) z & 0xffffffffL);
+        long mixed = surfaceMix(key);
+        stripes[(int) mixed & (SURFACE_CACHE_STRIPES - 1)]
+                .put((int) (mixed >>> 4) & (SURFACE_CACHE_STRIPE_SIZE - 1), new SurfaceSample(key, superSeed, height));
+    }
+
+    private static long surfaceMix(long key) {
+        long mixed = key ^ (key >>> 33);
+        mixed *= 0xff51afd7ed558ccdL;
+        mixed ^= mixed >>> 33;
+        return mixed;
+    }
+
+    private double surfaceHeight(double rx, double rz, long superSeed, IrisData data, Engine engine) {
         SurfaceCacheStripe[] stripes = surfaceCache(data, engine).stripes();
         double lowerX = Math.floor(rx / SURFACE_GRID) * SURFACE_GRID;
         double lowerZ = Math.floor(rz / SURFACE_GRID) * SURFACE_GRID;
         double dx = (rx - lowerX) / SURFACE_GRID;
         double dz = (rz - lowerZ) / SURFACE_GRID;
-        double northWest = cachedSurfaceHeight(lowerX, lowerZ, superSeed, stripes, data, engine, prepared);
+        double northWest = cachedSurfaceHeight(lowerX, lowerZ, superSeed, stripes, data, engine);
         if (dx == 0D && dz == 0D) {
             return northWest;
         }
         double north = dx == 0D ? northWest : IrisInterpolation.lerp(northWest,
-                cachedSurfaceHeight(lowerX + SURFACE_GRID, lowerZ, superSeed, stripes, data, engine, prepared), dx);
+                cachedSurfaceHeight(lowerX + SURFACE_GRID, lowerZ, superSeed, stripes, data, engine), dx);
         double smooth = north;
         if (dz != 0D) {
-            double southWest = cachedSurfaceHeight(lowerX, lowerZ + SURFACE_GRID, superSeed, stripes, data, engine, prepared);
+            double southWest = cachedSurfaceHeight(lowerX, lowerZ + SURFACE_GRID, superSeed, stripes, data, engine);
             double south = dx == 0D ? southWest : IrisInterpolation.lerp(southWest,
-                    cachedSurfaceHeight(lowerX + SURFACE_GRID, lowerZ + SURFACE_GRID, superSeed, stripes, data, engine, prepared), dx);
+                    cachedSurfaceHeight(lowerX + SURFACE_GRID, lowerZ + SURFACE_GRID, superSeed, stripes, data, engine), dx);
             smooth = IrisInterpolation.lerp(north, south, dz);
         }
         return surfaceDetail == 0D ? smooth
-                : smooth + ((prepared == null ? sampleHeight(rx, rz, superSeed, data, engine) : prepared.applyAsDouble(rx, rz)) - smooth) * surfaceDetail;
+                : smooth + (sampleHeight(rx, rz, superSeed, data, engine) - smooth) * surfaceDetail;
     }
 
     private double sampleHeight(double rx, double rz, long superSeed, IrisData data, Engine engine) {
@@ -350,21 +341,19 @@ public class IrisGenerator extends IrisRegistrant {
         return v;
     }
 
-    private double cachedSurfaceHeight(double x, double z, long superSeed, SurfaceCacheStripe[] stripes, IrisData data, Engine engine, DoubleBinaryOperator prepared) {
+    private double cachedSurfaceHeight(double x, double z, long superSeed, SurfaceCacheStripe[] stripes, IrisData data, Engine engine) {
         if (x != (int) x || z != (int) z) {
-            return prepared == null ? sampleHeight(x, z, superSeed, data, engine) : prepared.applyAsDouble(x, z);
+            return sampleHeight(x, z, superSeed, data, engine);
         }
         long key = ((long) (int) x << 32) | ((int) z & 0xffffffffL);
-        long mixed = key ^ (key >>> 33);
-        mixed *= 0xff51afd7ed558ccdL;
-        mixed ^= mixed >>> 33;
+        long mixed = surfaceMix(key);
         SurfaceCacheStripe stripe = stripes[(int) mixed & (SURFACE_CACHE_STRIPES - 1)];
         int slot = (int) (mixed >>> 4) & (SURFACE_CACHE_STRIPE_SIZE - 1);
         SurfaceSample cached = stripe.get(key, superSeed, slot);
         if (cached != null) {
             return cached.height();
         }
-        double height = prepared == null ? sampleHeight(x, z, superSeed, data, engine) : prepared.applyAsDouble(x, z);
+        double height = sampleHeight(x, z, superSeed, data, engine);
         stripe.put(slot, new SurfaceSample(key, superSeed, height));
         return height;
     }
@@ -457,7 +446,7 @@ public class IrisGenerator extends IrisRegistrant {
     private record SurfaceSample(long key, long seed, double height) {
     }
 
-    private static final class SurfaceCacheStripe {
+    static final class SurfaceCacheStripe {
         private final AtomicReferenceArray<SurfaceSample> entries = new AtomicReferenceArray<>(SURFACE_CACHE_STRIPE_SIZE);
 
         private SurfaceSample get(long key, long seed, int slot) {
diff --git a/core/src/main/java/art/arcane/iris/generation/noise/IrisNoiseGenerator.java b/core/src/main/java/art/arcane/iris/generation/noise/IrisNoiseGenerator.java
index 2793c4c23..1ea234e8c 100644
--- a/core/src/main/java/art/arcane/iris/generation/noise/IrisNoiseGenerator.java
+++ b/core/src/main/java/art/arcane/iris/generation/noise/IrisNoiseGenerator.java
@@ -39,6 +39,7 @@ import art.arcane.volmlib.util.noise.NoiseGenerator;
 import art.arcane.volmlib.util.noise.OffsetNoiseGenerator;
 import art.arcane.volmlib.util.noise.PerlinNoise;
 import art.arcane.volmlib.util.noise.SimplexNoise;
+import art.arcane.volmlib.util.noise.program.NoiseProgram;
 import lombok.AccessLevel;
 import lombok.AllArgsConstructor;
 import lombok.Data;
@@ -47,8 +48,8 @@ import lombok.NoArgsConstructor;
 import lombok.Setter;
 import lombok.experimental.Accessors;
 
+import java.util.Objects;
 import java.util.concurrent.atomic.AtomicReference;
-import java.util.function.DoubleBinaryOperator;
 
 @Snippet("generator")
 @Accessors(chain = true)
@@ -198,44 +199,29 @@ public class IrisNoiseGenerator {
         return true;
     }
 
-    DoubleBinaryOperator prepareBatch(long superSeed, IrisData data, Engine engine) {
+    NoiseLayerProgram compileProgram(long superSeed, IrisData data, Engine engine) {
         if (!enabled) {
-            double value = offsetY;
-            return (x, z) -> value;
+            return NoiseLayerProgram.disabled(this);
         }
-        if (hasDeepFracture()) {
-            FractureSamples samples = new FractureSamples();
-            if (samples.prepare(this, superSeed, data, engine)) {
-                return samples::sample;
+        int enabledChildren = 0;
+        for (IrisNoiseGenerator child : fracture) {
+            if (child.isEnabled()) {
+                enabledChildren++;
             }
         }
-        DoubleBinaryOperator[] children = new DoubleBinaryOperator[fracture.size()];
-        double[] offsets = new double[fracture.size()];
+        NoiseLayerProgram[] children = new NoiseLayerProgram[enabledChildren];
+        double[] offsets = new double[enabledChildren];
         int salt = 33;
-        for (int index = 0; index < children.length; index++) {
-            IrisNoiseGenerator child = fracture.get(index);
+        int compiled = 0;
+        for (IrisNoiseGenerator child : fracture) {
             if (child.isEnabled()) {
-                children[index] = child.prepareBatch(superSeed + seed + salt, data, engine);
-                offsets[index] = child.getOpacity() / 2D;
+                children[compiled] = child.compileProgram(superSeed + seed + salt, data, engine);
+                offsets[compiled++] = child.getOpacity() / 2D;
             }
             salt += 819;
         }
-        CNG generator = getGenerator(superSeed, data, engine);
-        return (x, z) -> samplePrepared(generator, children, offsets, x, z);
-    }
-
-    private double samplePrepared(CNG generator, DoubleBinaryOperator[] children, double[] offsets,
-                                  double xv, double zv) {
-        double x = xv;
-        double z = zv;
-        for (int index = 0; index < children.length; index++) {
-            DoubleBinaryOperator child = children[index];
-            if (child != null) {
-                x += child.applyAsDouble(xv, zv) - offsets[index];
-                z += child.applyAsDouble(zv, xv) - offsets[index];
-            }
-        }
-        return sample(generator, x, z);
+        CNG generator = Objects.requireNonNull(getGenerator(superSeed, data, engine), "Noise layer generator");
+        return NoiseLayerProgram.of(this, NoiseProgram.compile2D(generator), children, offsets);
     }
 
     public KList<IrisNoiseGenerator> getAllComposites() {
diff --git a/core/src/main/java/art/arcane/iris/generation/noise/NoiseLayerProgram.java b/core/src/main/java/art/arcane/iris/generation/noise/NoiseLayerProgram.java
new file mode 100644
index 000000000..e9bd1df41
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/noise/NoiseLayerProgram.java
@@ -0,0 +1,184 @@
+package art.arcane.iris.generation.noise;
+
+import art.arcane.volmlib.util.interpolation.IrisInterpolation;
+import art.arcane.volmlib.util.noise.program.NoiseProgram;
+
+import java.util.Arrays;
+
+public final class NoiseLayerProgram {
+    private final boolean enabled;
+    private final double offsetY;
+    private final NoiseProgram program;
+    private final double zoom;
+    private final double opacity;
+    private final double offsetX;
+    private final double offsetZ;
+    private final double exponent;
+    private final boolean negative;
+    private final boolean parametric;
+    private final boolean bezier;
+    private final boolean sinCentered;
+    private final NoiseLayerProgram[] children;
+    private final double[] childOffsets;
+
+    private NoiseLayerProgram(IrisNoiseGenerator layer, NoiseProgram program, NoiseLayerProgram[] children, double[] childOffsets) {
+        this.enabled = program != null;
+        this.offsetY = layer.getOffsetY();
+        this.program = program;
+        this.zoom = layer.getZoom();
+        this.opacity = layer.getOpacity();
+        this.offsetX = layer.getOffsetX();
+        this.offsetZ = layer.getOffsetZ();
+        this.exponent = layer.getExponent();
+        this.negative = layer.isNegative();
+        this.parametric = layer.isParametric();
+        this.bezier = layer.isBezier();
+        this.sinCentered = layer.isSinCentered();
+        this.children = children;
+        this.childOffsets = childOffsets;
+    }
+
+    static NoiseLayerProgram disabled(IrisNoiseGenerator layer) {
+        return new NoiseLayerProgram(layer, null, new NoiseLayerProgram[0], new double[0]);
+    }
+
+    static NoiseLayerProgram of(IrisNoiseGenerator layer, NoiseProgram program, NoiseLayerProgram[] children, double[] childOffsets) {
+        return new NoiseLayerProgram(layer, program, children, childOffsets);
+    }
+
+    public void evaluate(TerrainBatchScratch scratch, double[] xs, double[] zs, int count, double[] out) {
+        if (!enabled) {
+            Arrays.fill(out, 0, count, offsetY);
+            return;
+        }
+        int mark = scratch.mark();
+        double[] sampleX = scratch.buffer(count);
+        double[] sampleZ = scratch.buffer(count);
+        if (children.length == 0) {
+            for (int index = 0; index < count; index++) {
+                sampleX[index] = (xs[index] / zoom) + offsetX;
+                sampleZ[index] = (zs[index] / zoom) + offsetZ;
+            }
+        } else {
+            System.arraycopy(xs, 0, sampleX, 0, count);
+            System.arraycopy(zs, 0, sampleZ, 0, count);
+            double[] forward = scratch.buffer(count);
+            double[] reverse = scratch.buffer(count);
+            for (int child = 0; child < children.length; child++) {
+                children[child].evaluatePair(scratch, xs, zs, count, forward, reverse);
+                double offset = childOffsets[child];
+                for (int index = 0; index < count; index++) {
+                    sampleX[index] += forward[index] - offset;
+                    sampleZ[index] += reverse[index] - offset;
+                }
+            }
+            for (int index = 0; index < count; index++) {
+                sampleX[index] = (sampleX[index] / zoom) + offsetX;
+                sampleZ[index] = (sampleZ[index] / zoom) + offsetZ;
+            }
+        }
+        program.fill2D(scratch.noise(), sampleX, sampleZ, count, out);
+        for (int index = 0; index < count; index++) {
+            out[index] = post(out[index]);
+        }
+        scratch.reset(mark);
+    }
+
+    void evaluatePair(TerrainBatchScratch scratch, double[] xs, double[] zs, int count, double[] forward, double[] reverse) {
+        if (!enabled) {
+            Arrays.fill(forward, 0, count, offsetY);
+            Arrays.fill(reverse, 0, count, offsetY);
+            return;
+        }
+        int mark = scratch.mark();
+        int pairs = count * 2;
+        double[] sampleX = scratch.buffer(pairs);
+        double[] sampleZ = scratch.buffer(pairs);
+        System.arraycopy(xs, 0, sampleX, 0, count);
+        System.arraycopy(zs, 0, sampleZ, 0, count);
+        System.arraycopy(zs, 0, sampleX, count, count);
+        System.arraycopy(xs, 0, sampleZ, count, count);
+        if (children.length > 0) {
+            double[] childForward = scratch.buffer(count);
+            double[] childReverse = scratch.buffer(count);
+            for (int child = 0; child < children.length; child++) {
+                children[child].evaluatePair(scratch, xs, zs, count, childForward, childReverse);
+                double offset = childOffsets[child];
+                for (int index = 0; index < count; index++) {
+                    sampleX[index] += childForward[index] - offset;
+                    sampleZ[index] += childReverse[index] - offset;
+                    sampleX[count + index] += childReverse[index] - offset;
+                    sampleZ[count + index] += childForward[index] - offset;
+                }
+            }
+        }
+        for (int index = 0; index < pairs; index++) {
+            sampleX[index] = (sampleX[index] / zoom) + offsetX;
+            sampleZ[index] = (sampleZ[index] / zoom) + offsetZ;
+        }
+        double[] values = scratch.buffer(pairs);
+        program.fill2D(scratch.noise(), sampleX, sampleZ, pairs, values);
+        for (int index = 0; index < count; index++) {
+            forward[index] = post(values[index]);
+            reverse[index] = post(values[count + index]);
+        }
+        scratch.reset(mark);
+    }
+
+    public double sample(TerrainBatchScratch scratch, double x, double z) {
+        if (!enabled) {
+            return offsetY;
+        }
+        double sampleX = x;
+        double sampleZ = z;
+        if (children.length > 0) {
+            int mark = scratch.mark();
+            double[] pair = scratch.buffer(2);
+            for (int child = 0; child < children.length; child++) {
+                children[child].samplePair(scratch, x, z, pair);
+                double offset = childOffsets[child];
+                sampleX += pair[0] - offset;
+                sampleZ += pair[1] - offset;
+            }
+            scratch.reset(mark);
+        }
+        return post(program.sample2D((sampleX / zoom) + offsetX, (sampleZ / zoom) + offsetZ));
+    }
+
+    private void samplePair(TerrainBatchScratch scratch, double x, double z, double[] out) {
+        if (!enabled) {
+            out[0] = offsetY;
+            out[1] = offsetY;
+            return;
+        }
+        double forwardX = x;
+        double forwardZ = z;
+        double reverseX = z;
+        double reverseZ = x;
+        if (children.length > 0) {
+            int mark = scratch.mark();
+            double[] pair = scratch.buffer(2);
+            for (int child = 0; child < children.length; child++) {
+                children[child].samplePair(scratch, x, z, pair);
+                double offset = childOffsets[child];
+                forwardX += pair[0] - offset;
+                forwardZ += pair[1] - offset;
+                reverseX += pair[1] - offset;
+                reverseZ += pair[0] - offset;
+            }
+            scratch.reset(mark);
+        }
+        out[0] = post(program.sample2D((forwardX / zoom) + offsetX, (forwardZ / zoom) + offsetZ));
+        out[1] = post(program.sample2D((reverseX / zoom) + offsetX, (reverseZ / zoom) + offsetZ));
+    }
+
+    private double post(double raw) {
+        double n = raw * opacity;
+        n = negative ? (-n + opacity) : n;
+        n = (exponent != 1 ? n < 0 ? -Math.pow(-n, exponent) : Math.pow(n, exponent) : n) + offsetY;
+        n = parametric ? IrisInterpolation.parametric(n, 2D) : n;
+        n = bezier ? IrisInterpolation.bezier(n) : n;
+        n = sinCentered ? IrisInterpolation.sinCenter(n) : n;
+        return n;
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/noise/TerrainBatchScratch.java b/core/src/main/java/art/arcane/iris/generation/noise/TerrainBatchScratch.java
new file mode 100644
index 000000000..9cdaaa6eb
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/noise/TerrainBatchScratch.java
@@ -0,0 +1,115 @@
+package art.arcane.iris.generation.noise;
+
+import art.arcane.volmlib.util.noise.program.NoiseScratch;
+
+import java.util.Arrays;
+
+public final class TerrainBatchScratch {
+    private static final int MINIMUM_BUFFER = 256;
+
+    private final NoiseScratch noise = new NoiseScratch();
+    private double[][] buffers = new double[32][];
+    private int[][] indexBuffers = new int[8][];
+    private int top;
+    private int indexTop;
+    private long[] latticeX = new long[64];
+    private long[] latticeZ = new long[64];
+    private int[] latticeSlots = new int[64];
+    private int latticeCapacity = 64;
+    private int latticeCount;
+
+    public NoiseScratch noise() {
+        return noise;
+    }
+
+    public int mark() {
+        return top;
+    }
+
+    public int indexMark() {
+        return indexTop;
+    }
+
+    public void reset(int mark) {
+        top = mark;
+    }
+
+    public void resetIndices(int mark) {
+        indexTop = mark;
+    }
+
+    public double[] buffer(int length) {
+        if (top == buffers.length) {
+            buffers = Arrays.copyOf(buffers, top * 2);
+        }
+        double[] buffer = buffers[top];
+        if (buffer == null || buffer.length < length) {
+            buffer = new double[Math.max(length, MINIMUM_BUFFER)];
+            buffers[top] = buffer;
+        }
+        top++;
+        return buffer;
+    }
+
+    public int[] indices(int length) {
+        if (indexTop == indexBuffers.length) {
+            indexBuffers = Arrays.copyOf(indexBuffers, indexTop * 2);
+        }
+        int[] buffer = indexBuffers[indexTop];
+        if (buffer == null || buffer.length < length) {
+            buffer = new int[Math.max(length, MINIMUM_BUFFER)];
+            indexBuffers[indexTop] = buffer;
+        }
+        indexTop++;
+        return buffer;
+    }
+
+    void clearLattice(int maximumEntries) {
+        int capacity = Integer.highestOneBit(Math.max(16, maximumEntries * 2) - 1) << 1;
+        if (latticeSlots.length < capacity) {
+            latticeSlots = new int[capacity];
+        } else {
+            Arrays.fill(latticeSlots, 0, capacity, 0);
+        }
+        latticeCapacity = capacity;
+        latticeCount = 0;
+    }
+
+    int lattice(double x, double z) {
+        long xBits = Double.doubleToRawLongBits(x);
+        long zBits = Double.doubleToRawLongBits(z);
+        long mixed = xBits * 0x9E3779B97F4A7C15L ^ Long.rotateLeft(zBits * 0xC2B2AE3D27D4EB4FL, 31);
+        mixed ^= mixed >>> 29;
+        int mask = latticeCapacity - 1;
+        int slot = (int) mixed & mask;
+        while (true) {
+            int stored = latticeSlots[slot];
+            if (stored == 0) {
+                if (latticeCount == latticeX.length) {
+                    latticeX = Arrays.copyOf(latticeX, latticeCount * 2);
+                    latticeZ = Arrays.copyOf(latticeZ, latticeCount * 2);
+                }
+                latticeX[latticeCount] = xBits;
+                latticeZ[latticeCount] = zBits;
+                latticeSlots[slot] = ++latticeCount;
+                return latticeCount - 1;
+            }
+            if (latticeX[stored - 1] == xBits && latticeZ[stored - 1] == zBits) {
+                return stored - 1;
+            }
+            slot = (slot + 1) & mask;
+        }
+    }
+
+    int latticeCount() {
+        return latticeCount;
+    }
+
+    double latticeX(int index) {
+        return Double.longBitsToDouble(latticeX[index]);
+    }
+
+    double latticeZ(int index) {
+        return Double.longBitsToDouble(latticeZ[index]);
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/runtime/IrisComplex.java b/core/src/main/java/art/arcane/iris/generation/runtime/IrisComplex.java
index d7145e8eb..c995c2e27 100644
--- a/core/src/main/java/art/arcane/iris/generation/runtime/IrisComplex.java
+++ b/core/src/main/java/art/arcane/iris/generation/runtime/IrisComplex.java
@@ -18,7 +18,21 @@
 
 package art.arcane.iris.generation.runtime;
 
+import art.arcane.iris.generation.bake.BakePlane;
+import art.arcane.iris.generation.bake.BakeRegistry;
+import art.arcane.iris.generation.bake.ChunkBakeCache;
+import art.arcane.iris.generation.bake.ChunkPlanes;
+import art.arcane.iris.generation.bake.ColumnBake;
+import art.arcane.iris.generation.bake.GeneratorEvaluations;
+import art.arcane.iris.generation.bake.PlaneSource;
+import art.arcane.iris.generation.bake.TerrainProgram;
+import art.arcane.iris.generation.noise.TerrainBatchScratch;
+import art.arcane.iris.generation.simd.SimdSupport;
+import art.arcane.iris.generation.stream.BakedDoubleStream;
+import art.arcane.iris.generation.stream.BakedHeightStream;
+import art.arcane.iris.generation.stream.BakedStream;
 import art.arcane.iris.generation.stream.GenerationStreams;
+import art.arcane.iris.generation.stream.RarityStream;
 import art.arcane.iris.generation.stream.CachedDoubleStream2D;
 import art.arcane.iris.generation.stream.CachedStream2D;
 import art.arcane.iris.generation.stream.ProvisionalSampling;
@@ -118,14 +132,16 @@ import java.nio.file.Path;
 import java.util.function.BiFunction;
 
 @Data
-@EqualsAndHashCode(exclude = {"data", "gridBoundsCache", "sharedCornerBounds", "frozenInterpolators", "frozenGenerators", "inferredBiomeStreams", "hydrologyRuntime", "imageMapRuntime", "terrainEngine", "terrain3D", "hydrologyBanks3D"})
-@ToString(exclude = {"data", "gridBoundsCache", "sharedCornerBounds", "frozenInterpolators", "frozenGenerators", "inferredBiomeStreams", "hydrologyRuntime", "imageMapRuntime", "terrainEngine", "terrain3D", "hydrologyBanks3D"})
+@EqualsAndHashCode(exclude = {"data", "gridBoundsCache", "sharedCornerBounds", "terrainProgram", "bakeCache", "biomeRegistry", "regionRegistry", "blockRegistry", "regionSource", "baseBiomeSource", "caveSource", "rockSource", "fluidSource", "childStyleSeed", "inferredByType", "naturalHeightSource", "naturalTrueBiomeSource", "trueBiomeSource", "frozenInterpolators", "frozenGenerators", "inferredBiomeStreams", "hydrologyRuntime", "imageMapRuntime", "terrainEngine", "terrain3D", "hydrologyBanks3D"})
+@ToString(exclude = {"data", "gridBoundsCache", "sharedCornerBounds", "terrainProgram", "bakeCache", "biomeRegistry", "regionRegistry", "blockRegistry", "regionSource", "baseBiomeSource", "caveSource", "rockSource", "fluidSource", "childStyleSeed", "inferredByType", "naturalHeightSource", "naturalTrueBiomeSource", "trueBiomeSource", "frozenInterpolators", "frozenGenerators", "inferredBiomeStreams", "hydrologyRuntime", "imageMapRuntime", "terrainEngine", "terrain3D", "hydrologyBanks3D"})
 public class IrisComplex implements DataProvider {
     private static final NoiseBounds ZERO_NOISE_BOUNDS = new NoiseBounds(0D, 0D);
     private static final AtomicLong lastBoundsFailureLog = new AtomicLong(0L);
     private static final int GRID_BOUNDS_CACHE_SIZE = 8192;
     private static final int STUDIO_NOISE_CACHE_SIZE = 32_768;
     private static final int TERRAIN_COLUMN_CACHE_SIZE = 524_288;
+    private static final int BAKE_CHUNKS_PER_NOISE_CHUNK = 8;
+    private static final int HYDROLOGY_BAKE_BUDGET_SHARES = 2;
     /** One million corners: about 20 MB, roughly a 4000 by 4000 block area at the 4-block grid. */
     private static final int SHARED_CORNER_BOUNDS_CAPACITY = 1 << 20;
     /** The slope streams measure the rise across a run of this many blocks, so gradient is slope over run. */
@@ -141,6 +157,7 @@ public class IrisComplex implements DataProvider {
             IrisGenerator::getLoadKey,
             Comparator.nullsFirst(Comparator.naturalOrder())
     );
+    private static final ThreadLocal<TerrainBatchScratch> BATCH_SCRATCH = ThreadLocal.withInitial(TerrainBatchScratch::new);
     private static final InferredType[] INFERRED_BIOME_PREPARATION_ORDER = {
             InferredType.LAND,
             InferredType.CAVE,
@@ -153,6 +170,37 @@ public class IrisComplex implements DataProvider {
     private final int biomeBoundsSamplingStep;
     private transient volatile SharedCornerBounds sharedCornerBounds;
     @Getter(AccessLevel.NONE)
+    @Setter(AccessLevel.NONE)
+    private transient volatile TerrainProgram terrainProgram;
+    @Getter(AccessLevel.NONE)
+    private final transient ChunkBakeCache bakeCache;
+    @Getter(AccessLevel.NONE)
+    private final transient BakeRegistry<IrisBiome> biomeRegistry = new BakeRegistry<>();
+    @Getter(AccessLevel.NONE)
+    private final transient BakeRegistry<IrisRegion> regionRegistry = new BakeRegistry<>();
+    @Getter(AccessLevel.NONE)
+    private final transient BakeRegistry<NativeBlockState> blockRegistry = new BakeRegistry<>();
+    @Getter(AccessLevel.NONE)
+    private final transient long childStyleSeed;
+    @Getter(AccessLevel.NONE)
+    private final transient Map<InferredType, ProceduralStream<IrisBiome>> inferredByType;
+    @Getter(AccessLevel.NONE)
+    private final transient ProceduralStream<IrisRegion> regionSource;
+    @Getter(AccessLevel.NONE)
+    private final transient ProceduralStream<IrisBiome> baseBiomeSource;
+    @Getter(AccessLevel.NONE)
+    private final transient ProceduralStream<IrisBiome> caveSource;
+    @Getter(AccessLevel.NONE)
+    private final transient ProceduralStream<NativeBlockState> rockSource;
+    @Getter(AccessLevel.NONE)
+    private final transient ProceduralStream<NativeBlockState> fluidSource;
+    @Getter(AccessLevel.NONE)
+    private final transient ProceduralStream<Double> naturalHeightSource;
+    @Getter(AccessLevel.NONE)
+    private final transient ProceduralStream<IrisBiome> naturalTrueBiomeSource;
+    @Getter(AccessLevel.NONE)
+    private final transient ProceduralStream<IrisBiome> trueBiomeSource;
+    @Getter(AccessLevel.NONE)
     private final transient IrisInterpolator[] frozenInterpolators;
     @Getter(AccessLevel.NONE)
     private final transient IrisGenerator[][] frozenGenerators;
@@ -170,6 +218,9 @@ public class IrisComplex implements DataProvider {
     @Getter(AccessLevel.NONE)
     @Setter(AccessLevel.NONE)
     private transient boolean hydrologyNoiseCachesClosed;
+    @Getter(AccessLevel.NONE)
+    @Setter(AccessLevel.NONE)
+    private transient HydrologyNoiseCacheBudget.Reservation hydrologyBakeReservation;
     private RNG rng;
     private double fluidHeight;
     private IrisData data;
@@ -213,9 +264,6 @@ public class IrisComplex implements DataProvider {
     private ProceduralStream<Double> unblendedNaturalHeightStream;
     private final TransitionDisplacementField transitionDisplacement;
     private ProceduralStream<Double> heightStream;
-    @Getter(AccessLevel.NONE)
-    @Setter(AccessLevel.NONE)
-    private CachedDoubleStream2D cachedHeightStream;
     private ProceduralStream<Integer> roundedHeighteightStream;
     private ProceduralStream<Double> maxHeightStream;
     private ProceduralStream<Double> overlayStream;
@@ -279,6 +327,7 @@ public class IrisComplex implements DataProvider {
         IrisBiome emptyBiome = new IrisBiome().setInferredType(InferredType.CAVE);
         UUID focusUUID = UUID.nameUUIDFromBytes("focus".getBytes());
         this.rng = new RNG(engine.getSeedManager().getComplex());
+        childStyleSeed = IrisBiome.childStyleSeed(rng, 123);
         this.data = engine.getData();
         imageMapRuntime = IrisImageMapRuntime.compile(engine);
         double height = engine.getMaxHeight();
@@ -292,7 +341,8 @@ public class IrisComplex implements DataProvider {
         boolean buffetActive = biomeBuffet != null && !biomeBuffet.cells().isEmpty();
         focusBiome = buffetActive ? null : compatUsable(engine.getFocus());
         focusRegion = buffetActive ? null : compatUsable(engine.getFocusRegion());
-        Map<InferredType, ProceduralStream<IrisBiome>> inferredStreams = new HashMap<>();
+        Map<InferredType, ProceduralStream<IrisBiome>> inferredStreams = new EnumMap<>(InferredType.class);
+        inferredByType = inferredStreams;
         KList<IrisRegion> preparedRegions = new KList<>();
 
         if (focusBiome != null) {
@@ -365,54 +415,59 @@ public class IrisComplex implements DataProvider {
 
             return value;
         });
-        rockStream = engine.getDimension().getRockPalette().getLayerGenerator(rng.nextParallelRNG(45), data).stream()
+        bakeCache = new ChunkBakeCache(new BakeSource(), cacheSize * BAKE_CHUNKS_PER_NOISE_CHUNK);
+        rockSource = engine.getDimension().getRockPalette().getLayerGenerator(rng.nextParallelRNG(45), data).stream()
                 .select(engine.getDimension().getRockPalette().getBlockData(data));
-        fluidStream = engine.getDimension().getFluidPalette().getLayerGenerator(rng.nextParallelRNG(78), data).stream()
+        rockStream = new BakedStream<>(bakeCache, BakePlane.ROCK, rockSource);
+        fluidSource = engine.getDimension().getFluidPalette().getLayerGenerator(rng.nextParallelRNG(78), data).stream()
                 .select(engine.getDimension().getFluidPalette().getBlockData(data));
+        fluidStream = new BakedStream<>(bakeCache, BakePlane.FLUID, fluidSource);
         hydrologyFluidStreams = createHydrologyFluidStreams(engine.getDimension().getHydrology());
         regionStyleStream = engine.getDimension().getRegionStyle().create(rng.nextParallelRNG(883), getData()).stream()
                 .zoom(engine.getDimension().getRegionZoom());
         regionIdentityStream = regionStyleStream.fit(Integer.MIN_VALUE, Integer.MAX_VALUE);
-        regionStream = focusedRegions != null ? focusedRegions
-                : GenerationStreams.cache2D(RegionSelection.select(new RegionSelection.Options(
-                        engine.getDimension(), data, regionStyleStream, imageMapRuntime, null)),
-                        "regionStream", engine, cacheSize);
-        caveBiomeStream = GenerationStreams.cache2D(GenerationStreams.contextInjecting(regionStream, engine, (c, x, z) -> c.getRegion().get(x, z))
+        regionSource = focusedRegions != null ? focusedRegions
+                : RegionSelection.select(new RegionSelection.Options(
+                        engine.getDimension(), data, regionStyleStream, imageMapRuntime, null));
+        regionStream = focusedRegions != null ? focusedRegions : new BakedStream<>(bakeCache, BakePlane.REGION, regionSource);
+        caveSource = GenerationStreams.contextInjecting(regionStream, engine, (c, x, z) -> c.getRegion().get(x, z))
                 .convert((r) -> createInferredBiomeStream(r, InferredType.CAVE))
-                .convertAware2D(ProceduralStream::get), "caveBiomeStream", engine, cacheSize);
+                .convertAware2D(ProceduralStream::get);
+        caveBiomeStream = new BakedStream<>(bakeCache, BakePlane.CAVE_BIOME, caveSource);
         inferredStreams.put(InferredType.CAVE, caveBiomeStream);
-        landBiomeStream = GenerationStreams.cache2D(GenerationStreams.contextInjecting(regionStream, engine, (c, x, z) -> c.getRegion().get(x, z))
+        landBiomeStream = GenerationStreams.contextInjecting(regionStream, engine, (c, x, z) -> c.getRegion().get(x, z))
                 .convert((r) -> createInferredBiomeStream(r, InferredType.LAND))
-                .convertAware2D(ProceduralStream::get), "landBiomeStream", engine, cacheSize);
+                .convertAware2D(ProceduralStream::get);
         inferredStreams.put(InferredType.LAND, landBiomeStream);
-        seaBiomeStream = GenerationStreams.cache2D(GenerationStreams.contextInjecting(regionStream, engine, (c, x, z) -> c.getRegion().get(x, z))
+        seaBiomeStream = GenerationStreams.contextInjecting(regionStream, engine, (c, x, z) -> c.getRegion().get(x, z))
                 .convert((r) -> createInferredBiomeStream(r, InferredType.SEA))
-                .convertAware2D(ProceduralStream::get), "seaBiomeStream", engine, cacheSize);
+                .convertAware2D(ProceduralStream::get);
         inferredStreams.put(InferredType.SEA, seaBiomeStream);
-        shoreBiomeStream = GenerationStreams.cache2D(GenerationStreams.contextInjecting(regionStream, engine, (c, x, z) -> c.getRegion().get(x, z))
+        shoreBiomeStream = GenerationStreams.contextInjecting(regionStream, engine, (c, x, z) -> c.getRegion().get(x, z))
                 .convert((r) -> createInferredBiomeStream(r, InferredType.SHORE))
-                .convertAware2D(ProceduralStream::get), "shoreBiomeStream", engine, cacheSize);
+                .convertAware2D(ProceduralStream::get);
         inferredStreams.put(InferredType.SHORE, shoreBiomeStream);
         bridgeStream = focusedBiomes != null ? focusedBiomes.convert(IrisBiome::getInferredType) :
-                GenerationStreams.cache2D(ContinentGenerator.create(engine.getDimension(), rng, getData()).stream()
-                        .convert((v) -> v >= engine.getDimension().getLandChance() ? InferredType.SEA : InferredType.LAND), "bridgeStream", engine, cacheSize);
-        ProceduralStream<IrisBiome> proceduralBaseBiomeStream = focusedBiomes != null ? focusedBiomes :
-                GenerationStreams.cache2D(bridgeStream.convertAware2D((t, x, z) -> inferredStreams.get(t).get(x, z))
-                        .convertAware2D(this::implode), "baseBiomeStream", engine, cacheSize);
-        baseBiomeStream = focusedBiomes != null || !imageMapRuntime.has(IrisImageMapApplication.BIOME)
-                ? proceduralBaseBiomeStream : GenerationStreams.cache2D(ProceduralStream.of((x, z) -> {
+                ContinentGenerator.create(engine.getDimension(), rng, getData()).stream()
+                        .convert((v) -> v >= engine.getDimension().getLandChance() ? InferredType.SEA : InferredType.LAND);
+        ProceduralStream<IrisBiome> proceduralBaseBiomeStream = focusedBiomes != null ? focusedBiomes
+                : ProceduralStream.of(this::proceduralBaseBiome,
+                        (x, y, z) -> implode(inferredByType.get(bridgeStream.get(x, y, z)).get(x, z), x, z),
+                        Interpolated.of(value -> 0D, value -> null));
+        baseBiomeSource = focusedBiomes != null || !imageMapRuntime.has(IrisImageMapApplication.BIOME)
+                ? proceduralBaseBiomeStream : ProceduralStream.of((x, z) -> {
                     IrisBiome mapped = imageMapRuntime.sampleBiome(x, z);
                     return mapped == null ? proceduralBaseBiomeStream.get(x, z) : mapped;
                 }, (x, y, z) -> {
                     IrisBiome mapped = imageMapRuntime.sampleBiome(x, z);
                     return mapped == null ? proceduralBaseBiomeStream.get(x, y, z) : mapped;
-                }, proceduralBaseBiomeStream), "imageMappedBaseBiomeStream", engine, cacheSize);
+                }, proceduralBaseBiomeStream);
+        baseBiomeStream = focusedBiomes != null ? focusedBiomes : new BakedStream<>(bakeCache, BakePlane.BASE_BIOME, baseBiomeSource);
         proceduralTerrainHeight = new ProceduralTerrainHeightSampler(
                 (x, z) -> getHeight(engine, x, z, engine.getSeedManager().getHeight()),
                 engine.getDimension().getTerrainSamplingStep());
-        baseTerrainHeightStream = GenerationStreams.cache2DDouble(
-                ProceduralStream.ofDouble(this::sampleUnblendedNaturalTerrainHeight),
-                "baseTerrainHeightStream", engine, cacheSize);
+        baseTerrainHeightStream = new BakedDoubleStream(bakeCache, BakePlane.BASE_HEIGHT,
+                ProceduralStream.ofDouble(this::sampleUnblendedNaturalTerrainHeight));
         boolean terrain3DEnabled = false;
         for (IrisBiome biome : generatorBiomes) {
             if (biome.getTerrain3D() != null) {
@@ -427,18 +482,20 @@ public class IrisComplex implements DataProvider {
                 new Terrain3DRuntime.Options(engine.getSeedManager().getTerrain(), engine.getHeight(),
                         fluidHeight, data, terrain3DEnabled, TERRAIN_COLUMN_CACHE_SIZE));
         unblendedNaturalHeightStream = terrain3DEnabled
-                ? GenerationStreams.cache2DDouble(ProceduralStream.ofDouble(this::sampleTerrain3DHeight), "unblendedNaturalHeightStream", engine, cacheSize)
+                ? ProceduralStream.ofDouble(this::sampleTerrain3DHeight)
                 : baseTerrainHeightStream;
         transitionDisplacement = transitionGenerationPlan == null ? null : new TransitionDisplacementField(
                 transitionGenerationPlan, new TransitionDisplacementField.Sources(
                 (x, z) -> unblendedNaturalHeightStream.getDouble(x, z), engine.getHeight()));
-        naturalHeightStream = transitionDisplacement == null ? unblendedNaturalHeightStream
-                : GenerationStreams.cache2DDouble(ProceduralStream.ofDouble((x, z) -> transitionDisplacement.height(
-                blockCoordinate(x), blockCoordinate(z), unblendedNaturalHeightStream.getDouble(x, z))),
-                "naturalHeightStream", engine, cacheSize);
-        naturalTrueBiomeStream = focusedBiomes != null ? GenerationStreams.cache2D(focusedBiomes, "naturalTrueBiomeStream-focus", engine, cacheSize)
-                : GenerationStreams.cache2D(ProceduralStream.of(this::sampleNaturalTrueBiome, this::sampleNaturalTrueBiome,
-                Interpolated.of(value -> 0D, value -> null)), "naturalTrueBiomeStream", engine, cacheSize);
+        naturalHeightSource = transitionDisplacement == null
+                ? unblendedNaturalHeightStream
+                : ProceduralStream.ofDouble((x, z) -> transitionDisplacement.height(
+                blockCoordinate(x), blockCoordinate(z), unblendedNaturalHeightStream.getDouble(x, z)));
+        naturalHeightStream = new BakedDoubleStream(bakeCache, BakePlane.NATURAL_HEIGHT, naturalHeightSource);
+        naturalTrueBiomeSource = focusedBiomes != null ? focusedBiomes
+                : ProceduralStream.of(this::sampleNaturalTrueBiome, this::sampleNaturalTrueBiome,
+                Interpolated.of(value -> 0D, value -> null));
+        naturalTrueBiomeStream = new BakedStream<>(bakeCache, BakePlane.NATURAL_TRUE_BIOME, naturalTrueBiomeSource);
         IrisHydrology configuredHydrology = engine.getDimension().getHydrology();
         if (hydrologyActive(configuredHydrology)) {
             hydrologyRuntime = new IrisHydrologyRuntime(new IrisHydrologyRuntimeContext(
@@ -467,8 +524,8 @@ public class IrisComplex implements DataProvider {
                                 Math.max(4096, cacheSize), data, banks3D));
             }
         }
-        cachedHeightStream = new TerrainHeightStream(engine, cacheSize);
-        heightStream = cachedHeightStream;
+        heightStream = new BakedHeightStream(bakeCache, () -> terrainEngine.getPlatformHooks().isMainThread(),
+                this::nonblockingTerrainHeight, this::resolveHydrologyTerrainHeight);
         roundedHeighteightStream = GenerationStreams.contextInjecting(heightStream, engine, (c, x, z) -> c.getHeight().getDouble(x, z))
                 .round();
         slopeStream = GenerationStreams.contextInjecting(heightStream, engine, (c, x, z) -> c.getHeight().getDouble(x, z))
@@ -476,8 +533,9 @@ public class IrisComplex implements DataProvider {
         naturalSlopeStream = GenerationStreams.cache2DDouble(naturalHeightStream.slope(3), "naturalSlopeStream", engine, cacheSize);
         // Terrain3D column heights resolve the surface biome, so the shore band reads the pre-terrain3D slope or it recurses.
         shoreSlopeStream = terrain3DEnabled ? baseTerrainHeightStream.slope(3) : naturalSlopeStream;
-        trueBiomeStream = focusedBiomes != null ? GenerationStreams.cache2D(focusedBiomes, "trueBiomeStream-focus", engine, cacheSize) : GenerationStreams.cache2D(heightStream
-                .convertAware2D((terrainHeight, x, z) -> resolveHydrologySurfaceBiome(terrainHeight, x, z)), "trueBiomeStream", engine, cacheSize);
+        trueBiomeSource = focusedBiomes != null ? focusedBiomes
+                : heightStream.convertAware2D((terrainHeight, x, z) -> resolveHydrologySurfaceBiome(terrainHeight, x, z));
+        trueBiomeStream = new BakedStream<>(bakeCache, BakePlane.TRUE_BIOME, trueBiomeSource);
         riverDistanceStream = GenerationStreams.cache2DDouble(ProceduralStream.ofDouble(this::resolveHydrologyDistance), "riverDistanceStream", engine, cacheSize);
         riverFlowStream = GenerationStreams.cache2DDouble(ProceduralStream.ofDouble(this::resolveHydrologyFlow), "riverFlowStream", engine, cacheSize);
         riverCarveWeightStream = GenerationStreams.cache2DDouble(ProceduralStream.ofDouble(this::resolveHydrologyCarveWeight), "riverCarveWeightStream", engine, cacheSize);
@@ -518,17 +576,11 @@ public class IrisComplex implements DataProvider {
         return engine.isStudio() && !detached ? Math.max(configuredSize, STUDIO_NOISE_CACHE_SIZE) : configuredSize;
     }
 
-    public synchronized void ensureTerrainNoiseCacheSize(int minimumChunks) {
+    public void ensureTerrainNoiseCacheSize(int minimumChunks) {
         if (minimumChunks <= 0) {
             throw new IllegalArgumentException("Terrain noise cache size must be positive");
         }
-        CachedDoubleStream2D naturalCache = (CachedDoubleStream2D) naturalHeightStream;
-        if (naturalCache.getMaxSize() < minimumChunks * 256L) {
-            naturalCache.setMaximumChunks(minimumChunks);
-        }
-        if (cachedHeightStream.getMaxSize() < minimumChunks * 256L) {
-            cachedHeightStream.setMaximumChunks(minimumChunks);
-        }
+        bakeCache.ensureCapacity(minimumChunks * BAKE_CHUNKS_PER_NOISE_CHUNK);
     }
 
     void expandHydrologyNoiseCaches() {
@@ -578,6 +630,27 @@ public class IrisComplex implements DataProvider {
         hydrologyNoiseCaches = List.of();
     }
 
+    synchronized void reserveHydrologyBake(HydrologyNoiseCacheBudget budget) {
+        if (detached || hydrologyRuntime == null || hydrologyNoiseCachesClosed || hydrologyBakeReservation != null) {
+            return;
+        }
+        int capacity = bakeCache.capacity();
+        int requested = HydrologyNoiseCacheBudget.MAXIMUM_CHUNKS - capacity;
+        if (requested <= 0) {
+            return;
+        }
+        hydrologyBakeReservation = budget.reserve(HYDROLOGY_BAKE_BUDGET_SHARES, requested);
+        bakeCache.ensureCapacity(capacity + hydrologyBakeReservation.additionalChunks());
+    }
+
+    private synchronized void releaseHydrologyBake() {
+        if (hydrologyBakeReservation == null) {
+            return;
+        }
+        hydrologyBakeReservation.close();
+        hydrologyBakeReservation = null;
+    }
+
     void enablePreparedHydrologyCache(String runtimeIdentity, Path persistentRoot) {
         if (hydrologyRuntime != null) {
             hydrologyRuntime.enableSharedCache(runtimeIdentity, persistentRoot);
@@ -787,106 +860,261 @@ public class IrisComplex implements DataProvider {
         return true;
     }
 
-    private void sampleBaseHeightBatch(long[] coordinates, int count, double[] target) {
-        ((CachedDoubleStream2D) baseTerrainHeightStream).getBatch(coordinates, count, target, this::resolveBaseHeightBatch);
-    }
-
     private void resolveBaseHeightBatch(long[] missing, int size, double[] values) {
-        double[] xs = new double[size];
-        double[] zs = new double[size];
-        double[] lows = new double[size];
-        double[] highs = new double[size];
-        double[] activeXs = new double[size];
-        double[] activeZs = new double[size];
-        double[] noise = new double[size];
-        double[] groupHeights = new double[size];
-        int[] active = new int[size];
-        for (int index = 0; index < size; index++) {
-            xs[index] = RiverFootprint.unpackX(missing[index]);
-            zs[index] = RiverFootprint.unpackZ(missing[index]);
-        }
-        long seed = terrainEngine.getSeedManager().getHeight() + 239945;
-        for (int group = 0; group < frozenInterpolators.length; group++) {
-            IrisGenerator[] generators = frozenGenerators[group];
-            if (generators.length == 0) {
-                continue;
-            }
-            int activeCount = 0;
-            Arrays.fill(groupHeights, 0D);
+        TerrainBatchScratch scratch = BATCH_SCRATCH.get();
+        int mark = scratch.mark();
+        int indexMark = scratch.indexMark();
+        try {
+            double[] xs = scratch.buffer(size);
+            double[] zs = scratch.buffer(size);
+            double[] lows = scratch.buffer(size);
+            double[] highs = scratch.buffer(size);
+            Arrays.fill(values, 0, size, 0D);
             for (int index = 0; index < size; index++) {
-                NoiseBounds bounds = gridSampleBounds(terrainEngine, frozenInterpolators[group], group,
-                        generators, xs[index], zs[index]);
-                lows[index] = bounds.min();
-                highs[index] = bounds.max();
-                if (!Double.isFinite(lows[index]) || !Double.isFinite(highs[index])) {
-                    averageGeneratorHeights(generators, lows[index], highs[index], xs[index], zs[index], seed);
-                }
-                if (lows[index] != highs[index]) {
-                    active[activeCount] = index;
-                    activeXs[activeCount] = xs[index];
-                    activeZs[activeCount++] = zs[index];
-                } else {
-                    for (int generator = 0; generator < generators.length; generator++) {
-                        groupHeights[index] += lows[index];
-                    }
-                }
+                xs[index] = RiverFootprint.unpackX(missing[index]);
+                zs[index] = RiverFootprint.unpackZ(missing[index]);
             }
-            for (IrisGenerator generator : generators) {
-                if (activeCount == 0) {
-                    break;
+            TerrainProgram program = terrainProgram();
+            long evaluations = 0L;
+            for (int group = 0; group < frozenInterpolators.length; group++) {
+                if (frozenGenerators[group].length == 0) {
+                    continue;
                 }
-                generator.getHeights(activeXs, activeZs, seed, noise, activeCount);
-                if (GenerationCounter.ENABLED) {
-                    GenerationCounter.GENERATOR_EVALUATIONS.add(activeCount);
-                }
-                for (int sample = 0; sample < activeCount; sample++) {
-                    int index = active[sample];
-                    if (!Double.isFinite(noise[sample])) {
-                        throw new IllegalStateException("Terrain generator noise was not finite at " + xs[index] + "," + zs[index]
-                                + " (generator=" + generator.getLoadKey() + ", noise=" + noise[sample]
-                                + ", bounds=" + lows[index] + ".." + highs[index] + ").");
-                    }
-                    groupHeights[index] += M.lerp(lows[index], highs[index], noise[sample]);
+                for (int index = 0; index < size; index++) {
+                    NoiseBounds bounds = gridSampleBounds(terrainEngine, frozenInterpolators[group], group,
+                            frozenGenerators[group], xs[index], zs[index]);
+                    lows[index] = bounds.min();
+                    highs[index] = bounds.max();
                 }
+                evaluations += program.accumulate(group, scratch, xs, zs, size, lows, highs, values);
             }
+            GeneratorEvaluations.batched(evaluations);
             for (int index = 0; index < size; index++) {
-                values[index] += groupHeights[index] / generators.length;
+                values[index] = finishBaseHeight(xs[index], zs[index], values[index]);
             }
-        }
-        for (int index = 0; index < size; index++) {
-            double height = Math.max(Math.min(values[index] + fluidHeight + overlayStream.get(xs[index], zs[index]),
-                    terrainEngine.getHeight()), 0);
-            values[index] = imageMapRuntime.sampleTerrainHeight(xs[index], zs[index], height);
+        } finally {
+            scratch.reset(mark);
+            scratch.resetIndices(indexMark);
         }
     }
 
-    private void sampleUnblendedHeightBatch(long[] coordinates, int count, double[] target) {
-        if (terrain3D == null) {
-            sampleBaseHeightBatch(coordinates, count, target);
+    private void bakeBaseHeights(int chunkX, int chunkZ, long[] missing, double[] values) {
+        int originX = chunkX << 4;
+        int originZ = chunkZ << 4;
+        if (!supportsChunkHeightBatch()) {
+            for (int index = 0; index < 256; index++) {
+                if ((missing[index >>> 6] & (1L << (index & 63))) != 0L) {
+                    values[index] = sampleUnblendedNaturalTerrainHeight(originX + (index & 15), originZ + (index >> 4));
+                }
+            }
             return;
         }
-        ((CachedDoubleStream2D) unblendedNaturalHeightStream).getBatch(coordinates, count, target, (missing, size, values) -> {
-            long[] required = new long[size];
-            int requiredCount = 0;
-            for (int index = 0; index < size; index++) {
-                if (terrain3D.requiresBaseHeight(RiverFootprint.unpackX(missing[index]), RiverFootprint.unpackZ(missing[index]))) {
-                    required[requiredCount++] = missing[index];
+        TerrainBatchScratch scratch = BATCH_SCRATCH.get();
+        int mark = scratch.mark();
+        int indexMark = scratch.indexMark();
+        try {
+            double[] xs = scratch.buffer(256);
+            double[] zs = scratch.buffer(256);
+            double[] lows = scratch.buffer(256);
+            double[] highs = scratch.buffer(256);
+            double[] heights = scratch.buffer(256);
+            int[] columns = scratch.indices(256);
+            int count = 0;
+            for (int index = 0; index < 256; index++) {
+                if ((missing[index >>> 6] & (1L << (index & 63))) != 0L) {
+                    xs[count] = originX + (index & 15);
+                    zs[count] = originZ + (index >> 4);
+                    heights[count] = 0D;
+                    columns[count++] = index;
                 }
             }
-            if (requiredCount > 0) {
-                sampleBaseHeightBatch(required, requiredCount, new double[requiredCount]);
+            if (count == 0) {
+                return;
             }
-            for (int index = 0; index < size; index++) {
-                values[index] = sampleTerrain3DHeight(RiverFootprint.unpackX(missing[index]), RiverFootprint.unpackZ(missing[index]));
+            TerrainProgram program = terrainProgram();
+            GridBoundsCache cache = gridBoundsCache.get();
+            int grid = biomeBoundsSamplingStep;
+            boolean corners = ChunkCorners.supports(grid);
+            long evaluations = 0L;
+            for (int group = 0; group < frozenInterpolators.length; group++) {
+                if (frozenGenerators[group].length == 0) {
+                    continue;
+                }
+                if (corners) {
+                    if (!chunkCornerBounds(cache, group, grid, originX, originZ, xs, zs, count, lows, highs)) {
+                        continue;
+                    }
+                } else {
+                    for (int index = 0; index < count; index++) {
+                        NoiseBounds bounds = gridSampleBounds(terrainEngine, frozenInterpolators[group], group,
+                                frozenGenerators[group], xs[index], zs[index]);
+                        lows[index] = bounds.min();
+                        highs[index] = bounds.max();
+                    }
+                }
+                evaluations += program.accumulate(group, scratch, xs, zs, count, lows, highs, heights);
             }
-        });
+            for (int index = 0; index < count; index++) {
+                values[columns[index]] = finishBaseHeight(xs[index], zs[index], heights[index]);
+            }
+            GeneratorEvaluations.bakedChunk(evaluations);
+        } finally {
+            scratch.reset(mark);
+            scratch.resetIndices(indexMark);
+        }
+    }
+
+    private boolean chunkCornerBounds(GridBoundsCache cache, int group, int grid, int originX, int originZ,
+                                      double[] xs, double[] zs, int count, double[] lows, double[] highs) {
+        int cells = 16 / grid;
+        int stride = cells + 1;
+        long[] packed = new long[stride * stride];
+        boolean silent = true;
+        for (int row = 0; row < stride; row++) {
+            for (int column = 0; column < stride; column++) {
+                long corner = cornerBounds(cache, terrainEngine, frozenInterpolators[group], group,
+                        frozenGenerators[group], originX + column * grid, originZ + row * grid);
+                packed[row * stride + column] = corner;
+                silent &= silentBounds(corner);
+            }
+        }
+        if (silent) {
+            return false;
+        }
+        for (int index = 0; index < count; index++) {
+            double x = xs[index];
+            double z = zs[index];
+            int gx = ((int) Math.floor(x)) & ~(grid - 1);
+            int gz = ((int) Math.floor(z)) & ~(grid - 1);
+            double fx = (x - gx) / grid;
+            double fz = (z - gz) / grid;
+            int cornerIndex = ((gz - originZ) / grid) * stride + (gx - originX) / grid;
+            long b00 = packed[cornerIndex];
+            if (fx == 0D && fz == 0D) {
+                lows[index] = boundsLow(b00);
+                highs[index] = boundsHigh(b00);
+            } else if (fz == 0D) {
+                long b10 = packed[cornerIndex + 1];
+                lows[index] = biLerp(boundsLow(b00), boundsLow(b10), boundsLow(b00), boundsLow(b10), fx, fz);
+                highs[index] = biLerp(boundsHigh(b00), boundsHigh(b10), boundsHigh(b00), boundsHigh(b10), fx, fz);
+            } else if (fx == 0D) {
+                long b01 = packed[cornerIndex + stride];
+                lows[index] = biLerp(boundsLow(b00), boundsLow(b00), boundsLow(b01), boundsLow(b01), fx, fz);
+                highs[index] = biLerp(boundsHigh(b00), boundsHigh(b00), boundsHigh(b01), boundsHigh(b01), fx, fz);
+            } else {
+                long b10 = packed[cornerIndex + 1];
+                long b01 = packed[cornerIndex + stride];
+                long b11 = packed[cornerIndex + stride + 1];
+                lows[index] = biLerp(boundsLow(b00), boundsLow(b10), boundsLow(b01), boundsLow(b11), fx, fz);
+                highs[index] = biLerp(boundsHigh(b00), boundsHigh(b10), boundsHigh(b01), boundsHigh(b11), fx, fz);
+            }
+        }
+        return true;
+    }
+
+    private void prefetchBaseHeights(int chunkX, int chunkZ, long[] naturalMissing) {
+        ChunkPlanes.Plane base = bakeCache.plane(BakePlane.BASE_HEIGHT, chunkX, chunkZ);
+        int originX = chunkX << 4;
+        int originZ = chunkZ << 4;
+        long[] compute = new long[4];
+        boolean any = false;
+        for (int index = 0; index < 256; index++) {
+            if ((naturalMissing[index >>> 6] & (1L << (index & 63))) == 0L || base.ready(index)) {
+                continue;
+            }
+            int x = originX + (index & 15);
+            int z = originZ + (index >> 4);
+            if (terrain3D != null && !terrain3D.requiresBaseHeight(x, z)) {
+                continue;
+            }
+            compute[index >>> 6] |= 1L << (index & 63);
+            any = true;
+        }
+        if (!any) {
+            return;
+        }
+        double[] values = new double[256];
+        long revision = ProvisionalSampling.revision();
+        bakeBaseHeights(chunkX, chunkZ, compute, values);
+        if (revision != ProvisionalSampling.revision()) {
+            return;
+        }
+        for (int index = 0; index < 256; index++) {
+            if ((compute[index >>> 6] & (1L << (index & 63))) != 0L) {
+                base.storeDouble(index, values[index]);
+            }
+        }
+    }
+
+    private boolean supportsChunkHeightBatch() {
+        return terrainEngine.getDimension().getTerrainSamplingStep() == 1 && biomeBuffetGenerators.isEmpty()
+                && (biomeBuffet == null || biomeBuffet.cells().isEmpty());
+    }
+
+    private double finishBaseHeight(double x, double z, double interpolated) {
+        double height = Math.max(Math.min(interpolated + fluidHeight + overlayStream.get(x, z), terrainEngine.getHeight()), 0);
+        return imageMapRuntime.sampleTerrainHeight(x, z, height);
+    }
+
+    private TerrainProgram terrainProgram() {
+        TerrainProgram program = terrainProgram;
+        if (program == null) {
+            synchronized (this) {
+                program = terrainProgram;
+                if (program == null) {
+                    program = TerrainProgram.compile(frozenGenerators, terrainEngine.getSeedManager().getHeight() + 239945);
+                    terrainProgram = program;
+                }
+            }
+        }
+        return program;
+    }
+
+    private void sampleNaturalBatch(long[] coordinates, int count, double[] heights) {
+        long[] required = new long[count];
+        int requiredCount = 0;
+        for (int index = 0; index < count; index++) {
+            int x = RiverFootprint.unpackX(coordinates[index]);
+            int z = RiverFootprint.unpackZ(coordinates[index]);
+            if (bakedColumn(BakePlane.NATURAL_HEIGHT, x, z)
+                    || terrain3D != null && !terrain3D.requiresBaseHeight(x, z)
+                    || bakedColumn(BakePlane.BASE_HEIGHT, x, z)) {
+                continue;
+            }
+            required[requiredCount++] = coordinates[index];
+        }
+        if (requiredCount > 0) {
+            double[] baseHeights = new double[requiredCount];
+            long revision = ProvisionalSampling.revision();
+            resolveBaseHeightBatch(required, requiredCount, baseHeights);
+            if (bakeCache.memoAllowed()) {
+                for (int index = 0; index < requiredCount; index++) {
+                    bakeCache.storeDouble(BakePlane.BASE_HEIGHT, RiverFootprint.unpackX(required[index]),
+                            RiverFootprint.unpackZ(required[index]), baseHeights[index], revision);
+                }
+            }
+        }
+        for (int index = 0; index < count; index++) {
+            heights[index] = naturalHeightStream.getDouble(RiverFootprint.unpackX(coordinates[index]), RiverFootprint.unpackZ(coordinates[index]));
+        }
+    }
+
+    private IrisBiome proceduralBaseBiome(double x, double z) {
+        return implode(inferredByType.get(bridgeStream.get(x, z)).get(x, z), x, z);
+    }
+
+    private boolean bakedColumn(BakePlane plane, int blockX, int blockZ) {
+        ChunkPlanes.Plane values = bakeCache.planeIfPresent(plane, blockX >> 4, blockZ >> 4);
+        return values != null && values.ready(((blockZ & 15) << 4) | (blockX & 15));
     }
 
     private final class HydrologyHeightProvider implements IrisHydrologyNaturalHeightProvider {
         private final boolean batch = supportsHeightBatch();
+        private volatile boolean bakeReserved;
 
         @Override
         public double sample(int blockX, int blockZ) {
+            reserveBake();
             return naturalHeightStream.getDouble(blockX, blockZ);
         }
 
@@ -899,18 +1127,165 @@ public class IrisComplex implements DataProvider {
         public void sampleBatch(long[] coordinates, int count, double[] heights) {
             if (!batch) {
                 IrisHydrologyNaturalHeightProvider.super.sampleBatch(coordinates, count, heights);
-            } else if (transitionDisplacement == null) {
-                sampleUnblendedHeightBatch(coordinates, count, heights);
-            } else {
-                ((CachedDoubleStream2D) naturalHeightStream).getBatch(coordinates, count, heights, (missing, size, values) -> {
-                    sampleUnblendedHeightBatch(missing, size, values);
-                    for (int index = 0; index < size; index++) {
-                        values[index] = transitionDisplacement.height(RiverFootprint.unpackX(missing[index]),
-                                RiverFootprint.unpackZ(missing[index]), values[index]);
-                    }
-                });
+                return;
+            }
+            reserveBake();
+            sampleNaturalBatch(coordinates, count, heights);
+        }
+
+        private void reserveBake() {
+            if (bakeReserved) {
+                return;
+            }
+            bakeReserved = true;
+            reserveHydrologyBake(HydrologyNoiseCacheBudget.SHARED);
+        }
+    }
+
+    private final class BakeSource implements PlaneSource {
+        @Override
+        public void fill(BakePlane plane, int chunkX, int chunkZ, long[] missing, Object values) {
+            switch (plane) {
+                case REGION -> objectPlane(regionSource, chunkX, chunkZ, missing, (Object[]) values);
+                case BASE_BIOME -> objectPlane(baseBiomeSource, chunkX, chunkZ, missing, (Object[]) values);
+                case BASE_HEIGHT -> bakeBaseHeights(chunkX, chunkZ, missing, (double[]) values);
+                case NATURAL_HEIGHT -> naturalPlane(chunkX, chunkZ, missing, (double[]) values);
+                case NATURAL_TRUE_BIOME -> objectPlane(naturalTrueBiomeSource, chunkX, chunkZ, missing, (Object[]) values);
+                case HEIGHT -> heightPlane(chunkX, chunkZ, missing, (double[]) values);
+                case TRUE_BIOME -> objectPlane(trueBiomeSource, chunkX, chunkZ, missing, (Object[]) values);
+                case ROCK -> objectPlane(rockSource, chunkX, chunkZ, missing, (Object[]) values);
+                case FLUID -> objectPlane(fluidSource, chunkX, chunkZ, missing, (Object[]) values);
+                case CAVE_BIOME -> objectPlane(caveSource, chunkX, chunkZ, missing, (Object[]) values);
             }
         }
+
+        @Override
+        public ColumnBake assemble(ChunkPlanes planes) {
+            return assembleColumnBake(planes.chunkX(), planes.chunkZ());
+        }
+
+        @Override
+        public boolean mainThread() {
+            return terrainEngine.getPlatformHooks().isMainThread();
+        }
+
+        private void objectPlane(ProceduralStream<?> source, int chunkX, int chunkZ, long[] missing, Object[] values) {
+            int originX = chunkX << 4;
+            int originZ = chunkZ << 4;
+            for (int index = 0; index < 256; index++) {
+                if ((missing[index >>> 6] & (1L << (index & 63))) != 0L) {
+                    values[index] = source.get(originX + (index & 15), originZ + (index >> 4));
+                }
+            }
+        }
+
+        private void naturalPlane(int chunkX, int chunkZ, long[] missing, double[] values) {
+            prefetchBaseHeights(chunkX, chunkZ, missing);
+            int originX = chunkX << 4;
+            int originZ = chunkZ << 4;
+            for (int index = 0; index < 256; index++) {
+                if ((missing[index >>> 6] & (1L << (index & 63))) != 0L) {
+                    values[index] = naturalHeightSource.getDouble(originX + (index & 15), originZ + (index >> 4));
+                }
+            }
+        }
+
+        private void heightPlane(int chunkX, int chunkZ, long[] missing, double[] values) {
+            int originX = chunkX << 4;
+            int originZ = chunkZ << 4;
+            boolean main = terrainEngine.getPlatformHooks().isMainThread();
+            if (!main && !ChunkBakeCache.inSparseScope()) {
+                bakeCache.complete(BakePlane.NATURAL_HEIGHT, chunkX, chunkZ);
+            }
+            for (int index = 0; index < 256; index++) {
+                if ((missing[index >>> 6] & (1L << (index & 63))) != 0L) {
+                    int x = originX + (index & 15);
+                    int z = originZ + (index >> 4);
+                    values[index] = main ? nonblockingTerrainHeight(x, z) : resolveHydrologyTerrainHeight(x, z);
+                }
+            }
+        }
+    }
+
+    public Object bakePlane(BakePlane plane, int chunkX, int chunkZ) {
+        return bakeCache.complete(plane, chunkX, chunkZ);
+    }
+
+    public long[] bakeCensus() {
+        return bakeCache.census();
+    }
+
+    public ColumnBake columnBake(int chunkX, int chunkZ) {
+        return bakeCache.get(chunkX, chunkZ);
+    }
+
+    public ColumnBake columnBakeIfPresent(int chunkX, int chunkZ) {
+        return bakeCache.getIfPresent(chunkX, chunkZ);
+    }
+
+    public IrisBiome biome(int id) {
+        return id < 0 ? null : biomeRegistry.value(id);
+    }
+
+    public short biomeId(IrisBiome biome) {
+        return biome == null ? -1 : biomeRegistry.id(biome);
+    }
+
+    public IrisRegion region(int id) {
+        return id < 0 ? null : regionRegistry.value(id);
+    }
+
+    public short regionId(IrisRegion region) {
+        return region == null ? -1 : regionRegistry.id(region);
+    }
+
+    public NativeBlockState blockState(int id) {
+        return id < 0 ? null : blockRegistry.value(id);
+    }
+
+    private ColumnBake assembleColumnBake(int chunkX, int chunkZ) {
+        double[] height = (double[]) bakeCache.complete(BakePlane.HEIGHT, chunkX, chunkZ);
+        int[] rounded = new int[256];
+        SimdSupport.kernels().roundToInt(height, rounded, 256);
+        int originX = chunkX << 4;
+        int originZ = chunkZ << 4;
+        float[] fluidSurface = new float[256];
+        Terrain3DColumn[] terrainColumns = new Terrain3DColumn[256];
+        for (int index = 0; index < 256; index++) {
+            int x = originX + (index & 15);
+            int z = originZ + (index >> 4);
+            fluidSurface[index] = (float) riverWaterSurfaceStream.getDouble(x, z);
+            terrainColumns[index] = terrainColumn(x, z);
+        }
+        double[] apron = new double[ColumnBake.APRON_WIDTH * ColumnBake.APRON_WIDTH];
+        for (int row = 0; row < ColumnBake.APRON_WIDTH; row++) {
+            for (int column = 0; column < ColumnBake.APRON_WIDTH; column++) {
+                apron[row * ColumnBake.APRON_WIDTH + column] = heightStream.getDouble(originX - 1 + column, originZ - 1 + row);
+            }
+        }
+        return new ColumnBake(new ColumnBake.Planes(chunkX, chunkZ,
+                ids((Object[]) bakeCache.complete(BakePlane.REGION, chunkX, chunkZ), regionRegistry),
+                ids((Object[]) bakeCache.complete(BakePlane.BASE_BIOME, chunkX, chunkZ), biomeRegistry),
+                ids((Object[]) bakeCache.complete(BakePlane.TRUE_BIOME, chunkX, chunkZ), biomeRegistry),
+                ids((Object[]) bakeCache.complete(BakePlane.CAVE_BIOME, chunkX, chunkZ), biomeRegistry),
+                (double[]) bakeCache.complete(BakePlane.BASE_HEIGHT, chunkX, chunkZ),
+                (double[]) bakeCache.complete(BakePlane.NATURAL_HEIGHT, chunkX, chunkZ),
+                height,
+                rounded,
+                fluidSurface,
+                ids((Object[]) bakeCache.complete(BakePlane.ROCK, chunkX, chunkZ), blockRegistry),
+                ids((Object[]) bakeCache.complete(BakePlane.FLUID, chunkX, chunkZ), blockRegistry),
+                terrainColumns,
+                apron));
+    }
+
+    @SuppressWarnings("unchecked")
+    private static <T> short[] ids(Object[] values, BakeRegistry<T> registry) {
+        short[] ids = new short[values.length];
+        for (int index = 0; index < values.length; index++) {
+            ids[index] = values[index] == null ? -1 : registry.id((T) values[index]);
+        }
+        return ids;
     }
 
     private double sampleUnblendedNaturalTerrainHeight(double x, double z) {
@@ -993,29 +1368,29 @@ public class IrisComplex implements DataProvider {
             IrisBiome emptyBiome
     ) {
         return switch (inferredType) {
-            case CAVE -> engine.getDimension().getCaveBiomeStyle()
+            case CAVE -> new RarityStream<>(engine.getDimension().getCaveBiomeStyle()
                     .create(rng.nextParallelRNG(InferredType.CAVE.ordinal()), getData()).stream()
                     .zoom(engine.getDimension().getBiomeZoom())
-                    .zoom(region.getCaveBiomeZoom())
-                    .selectRarity(loadInferredBiomes(region.getCaveBiomes(), InferredType.CAVE))
+                    .zoom(region.getCaveBiomeZoom()),
+                    loadInferredBiomes(region.getCaveBiomes(), InferredType.CAVE))
                     .onNull(emptyBiome);
-            case LAND -> engine.getDimension().getLandBiomeStyle()
+            case LAND -> new RarityStream<>(engine.getDimension().getLandBiomeStyle()
                     .create(rng.nextParallelRNG(InferredType.LAND.ordinal()), getData()).stream()
                     .zoom(engine.getDimension().getBiomeZoom())
                     .zoom(engine.getDimension().getLandZoom())
-                    .zoom(region.getLandBiomeZoom())
-                    .selectRarity(loadInferredBiomes(region.getLandBiomes(), InferredType.LAND));
-            case SEA -> engine.getDimension().getSeaBiomeStyle()
+                    .zoom(region.getLandBiomeZoom()),
+                    loadInferredBiomes(region.getLandBiomes(), InferredType.LAND));
+            case SEA -> new RarityStream<>(engine.getDimension().getSeaBiomeStyle()
                     .create(rng.nextParallelRNG(InferredType.SEA.ordinal()), getData()).stream()
                     .zoom(engine.getDimension().getBiomeZoom())
                     .zoom(engine.getDimension().getSeaZoom())
-                    .zoom(region.getSeaBiomeZoom())
-                    .selectRarity(loadInferredBiomes(region.getSeaBiomes(), InferredType.SEA));
-            case SHORE -> engine.getDimension().getShoreBiomeStyle()
+                    .zoom(region.getSeaBiomeZoom()),
+                    loadInferredBiomes(region.getSeaBiomes(), InferredType.SEA));
+            case SHORE -> new RarityStream<>(engine.getDimension().getShoreBiomeStyle()
                     .create(rng.nextParallelRNG(InferredType.SHORE.ordinal()), getData()).stream()
                     .zoom(engine.getDimension().getBiomeZoom())
-                    .zoom(region.getShoreBiomeZoom())
-                    .selectRarity(loadInferredBiomes(region.getShoreBiomes(), InferredType.SHORE));
+                    .zoom(region.getShoreBiomeZoom()),
+                    loadInferredBiomes(region.getShoreBiomes(), InferredType.SHORE));
         };
     }
 
@@ -1646,7 +2021,7 @@ public class IrisComplex implements DataProvider {
         return biomeKey == null ? sample.parentBiomeKey() : biomeKey;
     }
 
-    private IrisBiome fixBiomeType(Double height, IrisBiome biome, IrisRegion region, Double x, Double z, double fluidHeight) {
+    private IrisBiome fixBiomeType(double height, IrisBiome biome, IrisRegion region, double x, double z, double fluidHeight) {
         IrisBiome resolved = resolveSurfaceBiome(
                 height,
                 biome,
@@ -1762,7 +2137,19 @@ public class IrisComplex implements DataProvider {
         double hi = sampledBounds.max();
         double lo = sampledBounds.min();
 
-        return averageGeneratorHeights(generators, lo, hi, x, z, seed + 239945);
+        return groupHeight(interpolatorIndex, generators, lo, hi, x, z, seed + 239945);
+    }
+
+    private double groupHeight(int group, IrisGenerator[] generators, double low, double high, double x, double z, long heightSeed) {
+        TerrainProgram program = terrainProgram;
+        if (program == null && terrainEngine != null) {
+            program = terrainProgram();
+        }
+        if (program == null || program.heightSeed() != heightSeed || group >= program.groups()
+                || program.groupSize(group) != generators.length || generators != frozenGenerators[group]) {
+            return averageGeneratorHeights(generators, low, high, x, z, heightSeed);
+        }
+        return program.average(group, BATCH_SCRATCH.get(), low, high, x, z);
     }
 
     private NoiseBounds gridSampleBounds(Engine engine, IrisInterpolator interpolator, int interpolatorIndex, IrisGenerator[] generators, double x, double z) {
@@ -1965,7 +2352,7 @@ public class IrisComplex implements DataProvider {
                 lo = biLerp(boundsLow(b00), boundsLow(b10), boundsLow(b01), boundsLow(b11), fx, fz);
                 hi = biLerp(boundsHigh(b00), boundsHigh(b10), boundsHigh(b01), boundsHigh(b11), fx, fz);
             }
-            h += averageGeneratorHeights(generators, lo, hi, x, z, heightSeed);
+            h += groupHeight(interpolatorIndex, generators, lo, hi, x, z, heightSeed);
         }
 
         return h;
@@ -2191,6 +2578,7 @@ public class IrisComplex implements DataProvider {
             }
             return height / generators.length;
         }
+        GeneratorEvaluations.scalar(generators.length);
         if (GenerationCounter.ENABLED) {
             GenerationCounter.GENERATOR_EVALUATIONS.add(generators.length);
         }
@@ -2264,7 +2652,7 @@ public class IrisComplex implements DataProvider {
         return computed;
     }
 
-    private IrisBiome implode(IrisBiome b, Double x, Double z) {
+    private IrisBiome implode(IrisBiome b, double x, double z) {
         if (b.getChildren().isEmpty()) {
             return b;
         }
@@ -2272,7 +2660,7 @@ public class IrisComplex implements DataProvider {
         return implode(b, x, z, 3);
     }
 
-    private IrisBiome implode(IrisBiome b, Double x, Double z, int max) {
+    private IrisBiome implode(IrisBiome b, double x, double z, int max) {
         if (max < 0) {
             return b;
         }
@@ -2281,7 +2669,7 @@ public class IrisComplex implements DataProvider {
             return b;
         }
 
-        CNG childCell = b.getChildrenGenerator(rng, 123, b.getChildShrinkFactor());
+        CNG childCell = b.getChildrenGenerator(childStyleSeed, b.getChildShrinkFactor());
         ChildSelectionPlan childSelectionPlan = resolveChildSelectionPlan(b);
         IrisBiome biome = childSelectionPlan.select(childCell, x, z).withInferredType(b.getInferredType());
         if (biome == b && hasFixedNoise(b.getChildStyle())) {
@@ -2504,7 +2892,8 @@ public class IrisComplex implements DataProvider {
             this.engine = engine;
             this.generators = generators;
             this.cachedBounds = cachedBounds;
-            this.integerCoordinates = complex.baseBiomeStream instanceof CachedStream2D<?>;
+            this.integerCoordinates = complex.baseBiomeStream instanceof BakedStream<?>
+                    || complex.baseBiomeStream instanceof CachedStream2D<?>;
             this.inUse = true;
             if (sampleSource.get() != complex.baseBiomeStream) {
                 sampleCache.clear();
@@ -2531,7 +2920,12 @@ public class IrisComplex implements DataProvider {
                 double sampleZ = integerCoordinates ? (int) zz : zz;
                 IrisBiome bx = sampleCache.get(sampleX, sampleZ);
                 if (bx == null) {
-                    bx = complex.baseBiomeStream.get(xx, zz);
+                    ChunkBakeCache.enterSparse();
+                    try {
+                        bx = complex.baseBiomeStream.get(xx, zz);
+                    } finally {
+                        ChunkBakeCache.exitSparse();
+                    }
                     sampleCache.put(sampleX, sampleZ, bx);
                 }
 
@@ -2601,62 +2995,6 @@ public class IrisComplex implements DataProvider {
         }
     }
 
-    private final class TerrainHeightStream extends CachedDoubleStream2D {
-        private TerrainHeightStream(Engine engine, int cacheSize) {
-            super("heightStream", engine, ProceduralStream.ofDouble(IrisComplex.this::resolveHydrologyTerrainHeight), cacheSize);
-        }
-
-        @Override
-        public double getDouble(double x, double z) {
-            return terrainEngine.getPlatformHooks().isMainThread()
-                    ? nonblockingTerrainHeight(x, z) : super.getDouble(x, z);
-        }
-
-        @Override
-        public Double get(double x, double y, double z) {
-            return getDouble(x, z);
-        }
-
-        @Override
-        public double getDouble(double x, double y, double z) {
-            return getDouble(x, z);
-        }
-
-        @Override
-        public void fillChunkDoubles(int worldX, int worldZ, double[] target) {
-            boolean mainThread = terrainEngine.getPlatformHooks().isMainThread();
-            if (!mainThread && (worldX & 15) == 0 && (worldZ & 15) == 0) {
-                super.fillChunkDoubles(worldX, worldZ, target);
-                return;
-            }
-            if (target == null || target.length != 256) {
-                throw new IllegalArgumentException("Expected a 16x16 target array.");
-            }
-            for (int index = 0; index < 256; index++) {
-                int x = worldX + (index & 15);
-                int z = worldZ + (index >> 4);
-                target[index] = mainThread ? nonblockingTerrainHeight(x, z) : super.getDouble(x, z);
-            }
-        }
-
-        @Override
-        public void fillChunkRaw(int worldX, int worldZ, Object[] target) {
-            boolean mainThread = terrainEngine.getPlatformHooks().isMainThread();
-            if (!mainThread && (worldX & 15) == 0 && (worldZ & 15) == 0) {
-                super.fillChunkRaw(worldX, worldZ, target);
-                return;
-            }
-            if (target == null || target.length != 256) {
-                throw new IllegalArgumentException("Expected a 16x16 target array.");
-            }
-            for (int index = 0; index < 256; index++) {
-                int x = worldX + (index & 15);
-                int z = worldZ + (index >> 4);
-                target[index] = mainThread ? nonblockingTerrainHeight(x, z) : super.getDouble(x, z);
-            }
-        }
-    }
-
     static final class ChildSelectionPlan {
         private final IrisRaritySelection<IrisBiome> selection;
 
@@ -2707,6 +3045,8 @@ public class IrisComplex implements DataProvider {
             hydrologyRuntime.close();
         }
         releaseHydrologyNoiseCaches();
+        releaseHydrologyBake();
+        bakeCache.clear();
         if (transitionDisplacement != null) {
             transitionDisplacement.clear();
         }
diff --git a/core/src/main/java/art/arcane/iris/generation/stream/BakedDoubleStream.java b/core/src/main/java/art/arcane/iris/generation/stream/BakedDoubleStream.java
new file mode 100644
index 000000000..5578bb160
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/stream/BakedDoubleStream.java
@@ -0,0 +1,92 @@
+package art.arcane.iris.generation.stream;
+
+import art.arcane.iris.generation.bake.BakePlane;
+import art.arcane.iris.generation.bake.ChunkBakeCache;
+import art.arcane.iris.generation.bake.ChunkPlanes;
+import art.arcane.volmlib.util.stream.BasicStream;
+import art.arcane.volmlib.util.stream.ProceduralStream;
+
+import java.util.Objects;
+
+public final class BakedDoubleStream extends BasicStream<Double> implements ChunkFillableStream2D, ChunkFillableDoubleStream2D {
+    private final ChunkBakeCache cache;
+    private final BakePlane plane;
+    private final ProceduralStream<Double> scalar;
+
+    public BakedDoubleStream(ChunkBakeCache cache, BakePlane plane, ProceduralStream<Double> scalar) {
+        super();
+        this.cache = Objects.requireNonNull(cache, "Bake cache");
+        this.plane = Objects.requireNonNull(plane, "Bake plane");
+        this.scalar = Objects.requireNonNull(scalar, "Scalar source");
+    }
+
+    @Override
+    public Double get(double x, double z) {
+        return getDouble(x, z);
+    }
+
+    @Override
+    public double getDouble(double x, double z) {
+        int blockX = (int) x;
+        int blockZ = (int) z;
+        int index = ((blockZ & 15) << 4) | (blockX & 15);
+        ChunkPlanes.Plane values = cache.planeIfPresent(plane, blockX >> 4, blockZ >> 4);
+        if (values != null && values.ready(index)) {
+            return values.doubleAt(index);
+        }
+        if (!cache.memoAllowed()) {
+            return scalar.getDouble(blockX, blockZ);
+        }
+        long revision = ProvisionalSampling.revision();
+        double value = scalar.getDouble(blockX, blockZ);
+        cache.storeDouble(plane, blockX, blockZ, value, revision);
+        return value;
+    }
+
+    @Override
+    public Double get(double x, double y, double z) {
+        return scalar.get(x, y, z);
+    }
+
+    @Override
+    public double getDouble(double x, double y, double z) {
+        return scalar.getDouble(x, y, z);
+    }
+
+    @Override
+    public double toDouble(Double t) {
+        return t;
+    }
+
+    @Override
+    public Double fromDouble(double d) {
+        return d;
+    }
+
+    @Override
+    public void fillChunkDoubles(int worldX, int worldZ, double[] target) {
+        if (target == null || target.length != 256) {
+            throw new IllegalArgumentException("Expected a 16x16 target array.");
+        }
+        int chunkX = worldX >> 4;
+        int chunkZ = worldZ >> 4;
+        if (cache.memoAllowed()) {
+            System.arraycopy(cache.complete(plane, chunkX, chunkZ), 0, target, 0, 256);
+            return;
+        }
+        int originX = chunkX << 4;
+        int originZ = chunkZ << 4;
+        for (int index = 0; index < 256; index++) {
+            target[index] = getDouble(originX + (index & 15), originZ + (index >> 4));
+        }
+    }
+
+    @Override
+    public void fillChunkRaw(int worldX, int worldZ, Object[] target) {
+        double[] values = new double[256];
+        fillChunkDoubles(worldX, worldZ, values);
+        for (int index = 0; index < 256; index++) {
+            target[index] = values[index];
+        }
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/stream/BakedHeightStream.java b/core/src/main/java/art/arcane/iris/generation/stream/BakedHeightStream.java
new file mode 100644
index 000000000..70efa9736
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/stream/BakedHeightStream.java
@@ -0,0 +1,100 @@
+package art.arcane.iris.generation.stream;
+
+import art.arcane.iris.generation.bake.BakePlane;
+import art.arcane.iris.generation.bake.ChunkBakeCache;
+import art.arcane.iris.generation.bake.ChunkPlanes;
+import art.arcane.volmlib.util.function.NoiseProvider;
+import art.arcane.volmlib.util.stream.BasicStream;
+
+import java.util.Objects;
+import java.util.function.BooleanSupplier;
+
+public final class BakedHeightStream extends BasicStream<Double> implements ChunkFillableStream2D, ChunkFillableDoubleStream2D {
+    private final ChunkBakeCache cache;
+    private final BooleanSupplier mainThread;
+    private final NoiseProvider nonblocking;
+    private final NoiseProvider resolved;
+
+    public BakedHeightStream(ChunkBakeCache cache, BooleanSupplier mainThread, NoiseProvider nonblocking, NoiseProvider resolved) {
+        super();
+        this.cache = Objects.requireNonNull(cache, "Bake cache");
+        this.mainThread = Objects.requireNonNull(mainThread, "Main thread check");
+        this.nonblocking = Objects.requireNonNull(nonblocking, "Nonblocking height");
+        this.resolved = Objects.requireNonNull(resolved, "Resolved height");
+    }
+
+    @Override
+    public Double get(double x, double z) {
+        return getDouble(x, z);
+    }
+
+    @Override
+    public double getDouble(double x, double z) {
+        if (mainThread.getAsBoolean()) {
+            return nonblocking.noise(x, z);
+        }
+        return column((int) x, (int) z, !ChunkBakeCache.inSparseScope());
+    }
+
+    @Override
+    public Double get(double x, double y, double z) {
+        return getDouble(x, z);
+    }
+
+    @Override
+    public double getDouble(double x, double y, double z) {
+        return getDouble(x, z);
+    }
+
+    @Override
+    public double toDouble(Double t) {
+        return t;
+    }
+
+    @Override
+    public Double fromDouble(double d) {
+        return d;
+    }
+
+    @Override
+    public void fillChunkDoubles(int worldX, int worldZ, double[] target) {
+        if (target == null || target.length != 256) {
+            throw new IllegalArgumentException("Expected a 16x16 target array.");
+        }
+        boolean main = mainThread.getAsBoolean();
+        boolean memo = !main && !ChunkBakeCache.inSparseScope();
+        if (memo && (worldX & 15) == 0 && (worldZ & 15) == 0) {
+            System.arraycopy(cache.complete(BakePlane.HEIGHT, worldX >> 4, worldZ >> 4), 0, target, 0, 256);
+            return;
+        }
+        for (int index = 0; index < 256; index++) {
+            int x = worldX + (index & 15);
+            int z = worldZ + (index >> 4);
+            target[index] = main ? nonblocking.noise(x, z) : column(x, z, memo);
+        }
+    }
+
+    @Override
+    public void fillChunkRaw(int worldX, int worldZ, Object[] target) {
+        double[] values = new double[256];
+        fillChunkDoubles(worldX, worldZ, values);
+        for (int index = 0; index < 256; index++) {
+            target[index] = values[index];
+        }
+    }
+
+    private double column(int x, int z, boolean memo) {
+        int index = ((z & 15) << 4) | (x & 15);
+        ChunkPlanes.Plane values = cache.planeIfPresent(BakePlane.HEIGHT, x >> 4, z >> 4);
+        if (values != null && values.ready(index)) {
+            return values.doubleAt(index);
+        }
+        if (!memo) {
+            return resolved.noise(x, z);
+        }
+        long revision = ProvisionalSampling.revision();
+        double value = resolved.noise(x, z);
+        cache.storeDouble(BakePlane.HEIGHT, x, z, value, revision);
+        return value;
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/stream/BakedStream.java b/core/src/main/java/art/arcane/iris/generation/stream/BakedStream.java
new file mode 100644
index 000000000..1a0594b73
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/stream/BakedStream.java
@@ -0,0 +1,71 @@
+package art.arcane.iris.generation.stream;
+
+import art.arcane.iris.generation.bake.BakePlane;
+import art.arcane.iris.generation.bake.ChunkBakeCache;
+import art.arcane.iris.generation.bake.ChunkPlanes;
+import art.arcane.volmlib.util.stream.BasicStream;
+import art.arcane.volmlib.util.stream.ProceduralStream;
+
+import java.util.Objects;
+
+public final class BakedStream<T> extends BasicStream<T> implements ChunkFillableStream2D {
+    private final ChunkBakeCache cache;
+    private final BakePlane plane;
+    private final ProceduralStream<T> scalar;
+
+    public BakedStream(ChunkBakeCache cache, BakePlane plane, ProceduralStream<T> scalar) {
+        super();
+        this.cache = Objects.requireNonNull(cache, "Bake cache");
+        this.plane = Objects.requireNonNull(plane, "Bake plane");
+        this.scalar = Objects.requireNonNull(scalar, "Scalar source");
+    }
+
+    @Override
+    @SuppressWarnings("unchecked")
+    public T get(double x, double z) {
+        int blockX = (int) x;
+        int blockZ = (int) z;
+        int index = ((blockZ & 15) << 4) | (blockX & 15);
+        ChunkPlanes.Plane values = cache.planeIfPresent(plane, blockX >> 4, blockZ >> 4);
+        if (values != null && values.ready(index)) {
+            return (T) values.objectAt(index);
+        }
+        if (!cache.memoAllowed()) {
+            return scalar.get(blockX, blockZ);
+        }
+        long revision = ProvisionalSampling.revision();
+        T value = scalar.get(blockX, blockZ);
+        cache.storeObject(plane, blockX, blockZ, value, revision);
+        return value;
+    }
+
+    @Override
+    public T get(double x, double y, double z) {
+        return scalar.get(x, y, z);
+    }
+
+    @Override
+    public double toDouble(T t) {
+        return scalar.toDouble(t);
+    }
+
+    @Override
+    public T fromDouble(double d) {
+        return scalar.fromDouble(d);
+    }
+
+    @Override
+    public void fillChunkRaw(int worldX, int worldZ, Object[] target) {
+        int chunkX = worldX >> 4;
+        int chunkZ = worldZ >> 4;
+        if (cache.memoAllowed()) {
+            System.arraycopy(cache.complete(plane, chunkX, chunkZ), 0, target, 0, 256);
+            return;
+        }
+        int originX = chunkX << 4;
+        int originZ = chunkZ << 4;
+        for (int index = 0; index < 256; index++) {
+            target[index] = get(originX + (index & 15), originZ + (index >> 4));
+        }
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/stream/RarityStream.java b/core/src/main/java/art/arcane/iris/generation/stream/RarityStream.java
new file mode 100644
index 000000000..2d85e06da
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/generation/stream/RarityStream.java
@@ -0,0 +1,64 @@
+package art.arcane.iris.generation.stream;
+
+import art.arcane.volmlib.util.math.Rarity;
+import art.arcane.volmlib.util.stream.BasicStream;
+import art.arcane.volmlib.util.stream.ProceduralStream;
+
+import java.util.List;
+import java.util.Objects;
+
+public final class RarityStream<T extends Rarity> extends BasicStream<T> {
+    private final ProceduralStream<?> noise;
+    private final Object[] options;
+    private final double[] cumulative;
+
+    public RarityStream(ProceduralStream<?> noise, List<T> options) {
+        super();
+        this.noise = Objects.requireNonNull(noise, "Rarity noise");
+        this.options = options.toArray();
+        this.cumulative = new double[this.options.length];
+        double buffer = 0;
+        for (int index = 0; index < this.options.length; index++) {
+            buffer += 1d / Rarity.get(this.options[index]);
+            cumulative[index] = buffer;
+        }
+    }
+
+    @Override
+    public T get(double x, double z) {
+        return pick(noise.getDouble(x, z));
+    }
+
+    @Override
+    public T get(double x, double y, double z) {
+        return pick(noise.getDouble(x, y, z));
+    }
+
+    @Override
+    public double toDouble(T t) {
+        return 0;
+    }
+
+    @Override
+    public T fromDouble(double d) {
+        return null;
+    }
+
+    @SuppressWarnings("unchecked")
+    public T pick(double noiseValue) {
+        int count = options.length;
+        if (count == 0) {
+            return null;
+        }
+        if (count == 1) {
+            return (T) options[0];
+        }
+        double threshold = cumulative[count - 1] * noiseValue;
+        for (int index = 0; index < count; index++) {
+            if (cumulative[index] >= threshold) {
+                return (T) options[index];
+            }
+        }
+        return (T) options[count - 1];
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/generation/terrain/RegionSelection.java b/core/src/main/java/art/arcane/iris/generation/terrain/RegionSelection.java
index 99a1d2678..9c6234f9c 100644
--- a/core/src/main/java/art/arcane/iris/generation/terrain/RegionSelection.java
+++ b/core/src/main/java/art/arcane/iris/generation/terrain/RegionSelection.java
@@ -3,6 +3,7 @@ package art.arcane.iris.generation.terrain;
 import art.arcane.iris.generation.biome.IrisBiome;
 import art.arcane.iris.generation.image.IrisImageMapRuntime;
 import art.arcane.iris.generation.image.IrisImageMapApplication;
+import art.arcane.iris.generation.stream.RarityStream;
 import art.arcane.iris.pack.loading.IrisData;
 import art.arcane.iris.studio.generation.BiomeBuffetLayout;
 import art.arcane.volmlib.util.collection.KList;
@@ -24,7 +25,7 @@ public final class RegionSelection {
                 regions.add(region);
             }
         }
-        ProceduralStream<IrisRegion> selected = options.style().selectRarity(regions);
+        ProceduralStream<IrisRegion> selected = new RarityStream<>(options.style(), regions);
         if (!options.imageMaps().has(IrisImageMapApplication.REGION)) {
             return selected;
         }
diff --git a/core/src/main/java/art/arcane/iris/structure/object/IrisObject.java b/core/src/main/java/art/arcane/iris/structure/object/IrisObject.java
index 239bb6e3a..9b0d1fd52 100644
--- a/core/src/main/java/art/arcane/iris/structure/object/IrisObject.java
+++ b/core/src/main/java/art/arcane/iris/structure/object/IrisObject.java
@@ -61,6 +61,7 @@ import java.io.InputStream;
 import java.io.OutputStream;
 import java.util.Map;
 import java.util.Objects;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantReadWriteLock;
 import java.util.function.BiConsumer;
@@ -144,6 +145,7 @@ public class IrisObject extends IrisRegistrant {
     protected transient AtomicCache<AxisAlignedBB> aabb = new AtomicCache<>();
     transient final AtomicCache<KList<IrisBlockVector>> surfaceSupportOffsets = new AtomicCache<>();
     transient final AtomicCache<FloatingObjectFootprint> floatingFootprint = new AtomicCache<>();
+    transient final ConcurrentHashMap<ObjectPlacementBake.Key, ObjectPlacementBake> placementBakes = new ConcurrentHashMap<>();
     @Getter
     @Setter
     private transient TreeGrounding treeGrounding;
diff --git a/core/src/main/java/art/arcane/iris/structure/object/IrisObjectPlacementRunner.java b/core/src/main/java/art/arcane/iris/structure/object/IrisObjectPlacementRunner.java
index 6a7a4b651..36d05ab82 100644
--- a/core/src/main/java/art/arcane/iris/structure/object/IrisObjectPlacementRunner.java
+++ b/core/src/main/java/art/arcane/iris/structure/object/IrisObjectPlacementRunner.java
@@ -30,7 +30,6 @@ import art.arcane.iris.generation.decoration.IrisVacuumSettings;
 import art.arcane.iris.world.entity.IrisMarker;
 
 import art.arcane.iris.pack.loading.IrisData;
-import art.arcane.iris.generation.runtime.GenerationFailures;
 import art.arcane.iris.generation.runtime.IrisComplex;
 import art.arcane.iris.generation.runtime.Engine;
 import art.arcane.volmlib.nativelib.terrain.structure.NativeStructureVolume;
@@ -52,6 +51,7 @@ import art.arcane.volmlib.util.matter.MatterMarker;
 import it.unimi.dsi.fastutil.longs.Long2LongOpenHashMap;
 
 import java.util.Comparator;
+import java.util.IdentityHashMap;
 import java.util.Objects;
 import java.util.Optional;
 import java.util.Set;
@@ -475,127 +475,53 @@ final class IrisObjectPlacementRunner {
         int vacuumLowest = Integer.MAX_VALUE;
         int vacuumHighest = Integer.MIN_VALUE;
         self.readLock.lock();
-
-        KMap<IrisBlockVector, String> markers = null;
-
         try {
-            VectorMap<NativeBlockState> blocks = self.blocks;
-            VectorMap<TileData> states = self.states;
-            TreeGrounding tree = self.getTreeGrounding();
-            // Zero-tile objects are the common case: skip the two Key allocations VectorMap#get needs to prove null.
-            boolean hasStates = !states.isEmpty();
+            ObjectPlacementBake bake = ObjectPlacementBake.of(self, spin, ceilingHang, translating ? translateOffset : null);
+            PlacementStates palette = new PlacementStates(bake.palette(), config.getRotation(), spinx, spiny, spinz,
+                    preventingDecay, placer.isDebugSmartBore(), excludedStiltMaterials);
+            double[] exact = warped || hasEdits || eroding ? bake.exact(self, spin) : null;
+            String[] markers = config.getMarkers().isNotEmpty() && placer.getEngine() != null
+                    ? resolveMarkers(config, rng, x, yv, z, rdata, bake) : null;
+            int[] tileBlocks = bake.tileBlocks();
+            TileData[] tileValues = bake.tileValues();
+            int tileCursor = 0;
+            int count = bake.count();
 
-            if (config.getMarkers().isNotEmpty() && placer.getEngine() != null) {
-                markers = new KMap<>();
-                KList<IrisBlockVector> list = StreamSupport.stream(blocks.keys().spliterator(), false)
-                        .collect(KList.collector());
-                // Marker selection persists into the mantle, so it must be seed-deterministic.
-                // Derive a side stream keyed on the placement position instead of consuming the
-                // caller's rng: consuming draws there would shift every later placement in the
-                // chunk and invalidate existing worlds/goldenhashes.
-                RNG markerRng = rng.nextParallelRNG(((((long) x) << 32) | (z & 0xFFFFFFFFL)) * 31L + yv);
-
-                int markerIndex = 0;
-                for (IrisObjectMarker j : config.getMarkers()) {
-                    IrisMarker marker = self.getLoader().getMarkerLoader().load(j.getMarker());
-                    int markerSalt = markerIndex++;
-
-                    if (marker == null || marker.isCompatExcluded()) {
-                        continue;
-                    }
-
-                    int max = j.getMaximumMarkers();
-                    for (IrisBlockVector i : list.shuffleCopy(markerRng.nextParallelRNG(markerSalt))) {
-                        if (max <= 0) {
-                            break;
-                        }
-
-                        NativeBlockState data = blocks.get(i);
-                        if (data == null) {
-                            continue;
-                        }
-
-                        for (NativeBlockState k : j.getMark(rdata)) {
-                            if (max <= 0) {
-                                break;
-                            }
-
-                            if (j.isExact() ? k.matches(data) : IrisObjectShaping.materialKey(k).equals(IrisObjectShaping.materialKey(data))) {
-                                boolean a = !blocks.containsKey((IrisBlockVector) i.clone().add(new IrisBlockVector(0, 1, 0)));
-                                boolean fff = !blocks.containsKey((IrisBlockVector) i.clone().add(new IrisBlockVector(0, 2, 0)));
-
-                                if (!marker.isEmptyAbove() || (a && fff)) {
-                                    markers.put(i, j.getMarker());
-                                    max--;
-                                }
-                            }
-                        }
-                    }
-                }
-            }
-
-            VectorMap<NativeBlockState>.Cursor cursor = blocks.cursor();
-            while (cursor.next()) {
-                IrisBlockVector g = cursor.key();
-                NativeBlockState d;
+            for (int index = 0; index < count; index++) {
+                int entry = bake.paletteIndex(index);
                 TileData tile = null;
+                if (tileBlocks != null && tileCursor < tileBlocks.length && tileBlocks[tileCursor] == index) {
+                    tile = tileValues[tileCursor++];
+                }
 
-                try {
-                    d = cursor.value();
-                    if (hasStates) {
-                        tile = states.get(g);
+                if (stilting && palette.stiltLayer(entry)) {
+                    int layer = bake.layerY(index);
+                    if (layer < lowest) {
+                        lowest = layer;
                     }
-                } catch (Throwable e) {
-                    GenerationFailures.rethrowEngineFailure(e);
-                    IrisLogging.reportError(e);
-                    IrisLogging.warn("Failed to read block node " + g.getBlockX() + "," + g.getBlockY() + "," + g.getBlockZ() + " in object " + self.getLoadKey() + " (cme)");
-                    d = IrisObject.States.air();
-                }
-
-                if (d == null) {
-                    IrisLogging.warn("Failed to read block node " + g.getBlockX() + "," + g.getBlockY() + "," + g.getBlockZ() + " in object " + self.getLoadKey() + " (null)");
-                    d = IrisObject.States.air();
-                }
-
-                if (placer.isDebugSmartBore() && IrisObject.States.vair().equals(d)) {
-                    d = IrisObject.States.vairDebug();
-                }
-
-                NativeBlockState data = d;
-                IrisBlockVector i = g.clone();
-                spin.rotate(i);
-                if (ceilingHang) {
-                    i.setY(-i.getBlockY());
-                }
-                if (translating) {
-                    i.add(translateOffset);
-                }
-
-                if (stilting && IrisObjectShaping.isStiltLayerBlock(data)) {
-                    if (i.getBlockY() < lowest) {
-                        lowest = i.getBlockY();
-                    }
-                    if (i.getBlockY() > topLayer) {
-                        topLayer = i.getBlockY();
+                    if (layer > topLayer) {
+                        topLayer = layer;
                     }
                 }
 
-                if (preventingDecay && IrisProceduralBlocks.hasProperty(data, "distance") && "false".equals(IrisProceduralBlocks.propertyValue(data, "persistent"))) {
-                    data = data.withProperty("persistent", "true");
-                }
-
+                NativeBlockState data = palette.decayed(entry);
+                boolean edited = false;
                 if (hasEdits) {
+                    double exactX = exact[index * 3];
+                    double exactY = exact[index * 3 + 1];
+                    double exactZ = exact[index * 3 + 2];
                     for (IrisObjectReplace j : config.getEdit()) {
                         if (rng.chance(j.getChance())) {
                             for (NativeBlockState k : j.getFind(rdata)) {
                                 if (j.isExact() ? k.matches(data) : IrisObjectShaping.materialKey(k).equals(IrisObjectShaping.materialKey(data))) {
-                                    NativeBlockState newData = j.getReplace(rng, i.getX() + x, i.getY() + y, i.getZ() + z, rdata);
+                                    NativeBlockState newData = j.getReplace(rng, exactX + x, exactY + y, exactZ + z, rdata);
 
                                     boolean sameMaterial = IrisObjectShaping.materialKey(newData).equals(IrisObjectShaping.materialKey(data));
                                     if (sameMaterial && !(newData.isCustom() || data.isCustom()))
                                         data = BlockDataMergeSupport.merge(data, newData);
                                     else
                                         data = newData;
+                                    edited = true;
 
                                     Optional<TileData> t = j.getReplace().getTile(rng, x, y, z, rdata);
                                     if (t.isPresent()) {
@@ -609,18 +535,21 @@ final class IrisObjectPlacementRunner {
                     }
                 }
 
-                data = config.getRotation().rotate(data, spinx, spiny, spinz);
-                if (data == null) {
+                StateFacts facts = edited ? palette.factsOf(data) : palette.facts(entry);
+                NativeBlockState rotated = facts.rotated();
+                if (rotated == null) {
                     continue;
                 }
-                xx = x + (int) Math.round(i.getX());
-
-                int yy = y + (int) Math.round(i.getY());
-                zz = z + (int) Math.round(i.getZ());
+                xx = x + bake.offsetX(index);
+                int yy = y + bake.offsetY(index);
+                zz = z + bake.offsetZ(index);
 
                 if (warped) {
-                    xx += surfaceWarp.fitDouble(-warpHalf, warpHalf, i.getX() + x, i.getY() + y, i.getZ() + z);
-                    zz += surfaceWarp.fitDouble(-warpHalf, warpHalf, i.getZ() + z, i.getY() + y, i.getX() + x);
+                    double exactX = exact[index * 3];
+                    double exactY = exact[index * 3 + 1];
+                    double exactZ = exact[index * 3 + 2];
+                    xx += surfaceWarp.fitDouble(-warpHalf, warpHalf, exactX + x, exactY + y, exactZ + z);
+                    zz += surfaceWarp.fitDouble(-warpHalf, warpHalf, exactZ + z, exactY + y, exactX + x);
                 }
 
                 if (paint) {
@@ -628,8 +557,8 @@ final class IrisObjectPlacementRunner {
                     if (surface == IrisPaintSurfaceProjection.MISSING) {
                         continue;
                     }
-                    if (!B.isVineBlock(data)) {
-                        yy = (int) Math.round(i.getY()) + Math.floorDiv(self.h, 2) + surface + yrand;
+                    if (!B.isVineBlock(rotated)) {
+                        yy = bake.offsetY(index) + Math.floorDiv(self.h, 2) + surface + yrand;
                     }
                 }
 
@@ -637,13 +566,18 @@ final class IrisObjectPlacementRunner {
                     continue;
                 }
 
-                boolean canopy = tree != null && tree.isCanopy(g.getBlockX(), g.getBlockY(), g.getBlockZ());
+                boolean canopy = bake.canopy(index);
                 if (canopy && !placer.beginTreeCanopy(new BlockPosition(xx, yy, zz))) {
                     continue;
                 }
 
                 try {
-                    data = normalizePlacedWaterlogging(data, placer, xx, yy, zz, waterlogCandidate);
+                    data = rotated;
+                    if (facts.waterloggable()) {
+                        data = waterlogCandidate || facts.authoredWaterlogged()
+                                ? IrisProceduralBlocks.normalizeWaterlogging(data, placer.get(xx, yy, zz), waterlogCandidate)
+                                : facts.dry();
+                    }
 
                     if (!rawStructurePiece && B.isVineBlock(data)) {
                         data = attachVineFaces(placer, data, xx, yy, zz);
@@ -652,9 +586,7 @@ final class IrisObjectPlacementRunner {
                     // Short-circuit order matters for cost only: the mantle read is paid solely
                     // for vine blocks. Both operands are pure, so the value is unchanged.
                     boolean wouldReplace = !rawStructurePiece && B.isVineBlock(data) && B.isSolid(placer.get(xx, yy, zz));
-                    String material = IrisObjectShaping.materialKey(data);
-                    boolean air = material.equals("minecraft:air") || material.equals("minecraft:cave_air");
-                    boolean place = shouldPlaceObjectBlock(rawStructurePiece, air, wouldReplace);
+                    boolean place = shouldPlaceObjectBlock(rawStructurePiece, facts.air(), wouldReplace);
 
                     if (data.isCustom() || place) {
                         placer.set(xx, yy, zz, data);
@@ -668,8 +600,8 @@ final class IrisObjectPlacementRunner {
                         if (tile != null) {
                             placer.setTile(xx, yy, zz, tile);
                         }
-                        if (markers != null && markers.containsKey(g)) {
-                            placer.setData(xx, yy, zz, new MatterMarker(markers.get(g)));
+                        if (markers != null && markers[index] != null) {
+                            placer.setData(xx, yy, zz, new MatterMarker(markers[index]));
                         }
                         if (listener != null) {
                             listener.accept(new BlockPosition(xx, yy, zz), data);
@@ -687,27 +619,21 @@ final class IrisObjectPlacementRunner {
                     }
                 }
             }
-        } finally {
-            self.readLock.unlock();
-        }
 
-        if (grounding != null) {
-            for (TreeGrounding.Extension extension : grounding.extensions()) {
-                for (int rootY = extension.topY(); rootY >= extension.bottomY(); rootY--) {
-                    NativeBlockState rootState = normalizePlacedWaterlogging(extension.state(), placer,
-                            extension.x(), rootY, extension.z(), waterlogCandidate);
-                    placer.set(extension.x(), rootY, extension.z(), rootState);
-                    if (listener != null) {
-                        listener.accept(new BlockPosition(extension.x(), rootY, extension.z()), rootState);
+            if (grounding != null) {
+                for (TreeGrounding.Extension extension : grounding.extensions()) {
+                    for (int rootY = extension.topY(); rootY >= extension.bottomY(); rootY--) {
+                        NativeBlockState rootState = normalizePlacedWaterlogging(extension.state(), placer,
+                                extension.x(), rootY, extension.z(), waterlogCandidate);
+                        placer.set(extension.x(), rootY, extension.z(), rootState);
+                        if (listener != null) {
+                            listener.accept(new BlockPosition(extension.x(), rootY, extension.z()), rootState);
+                        }
                     }
                 }
             }
-        }
 
-        if (stilting) {
-            self.readLock.lock();
-            try {
-                VectorMap<NativeBlockState> blocks = self.blocks;
+            if (stilting) {
                 IrisStiltSettings settings = stiltSettings;
 
                 double erodeCentroidX = 0;
@@ -715,93 +641,51 @@ final class IrisObjectPlacementRunner {
                 double erodeMaxDist = 1;
                 if (eroding) {
                     int centroidCount = 0;
-                    VectorMap<NativeBlockState>.Cursor centroidCursor = blocks.cursor();
-                    while (centroidCursor.next()) {
-                        IrisBlockVector rot = centroidCursor.key().clone();
-                        spin.rotate(rot);
-                        if (translating) {
-                            rot.add(translateOffset);
-                        }
-                        if (rot.getBlockY() == lowest) {
-                            NativeBlockState bd = centroidCursor.value();
-                            if (bd != null && IrisObjectShaping.shouldStilt(bd, excludedStiltMaterials)) {
-                                erodeCentroidX += rot.getX();
-                                erodeCentroidZ += rot.getZ();
-                                centroidCount++;
-                            }
+                    for (int index = 0; index < count; index++) {
+                        if (bake.layerY(index) == lowest && palette.shouldStilt(bake.paletteIndex(index))) {
+                            erodeCentroidX += exact[index * 3];
+                            erodeCentroidZ += exact[index * 3 + 2];
+                            centroidCount++;
                         }
                     }
                     if (centroidCount > 0) {
                         erodeCentroidX /= centroidCount;
                         erodeCentroidZ /= centroidCount;
                     }
-                    VectorMap<NativeBlockState>.Cursor spreadCursor = blocks.cursor();
-                    while (spreadCursor.next()) {
-                        IrisBlockVector rot = spreadCursor.key().clone();
-                        spin.rotate(rot);
-                        if (translating) {
-                            rot.add(translateOffset);
-                        }
-                        if (rot.getBlockY() == lowest) {
-                            NativeBlockState bd = spreadCursor.value();
-                            if (bd != null && IrisObjectShaping.shouldStilt(bd, excludedStiltMaterials)) {
-                                double dx = rot.getX() - erodeCentroidX;
-                                double dz = rot.getZ() - erodeCentroidZ;
-                                double dist = Math.sqrt(dx * dx + dz * dz);
-                                if (dist > erodeMaxDist) {
-                                    erodeMaxDist = dist;
-                                }
+                    for (int index = 0; index < count; index++) {
+                        if (bake.layerY(index) == lowest && palette.shouldStilt(bake.paletteIndex(index))) {
+                            double dx = exact[index * 3] - erodeCentroidX;
+                            double dz = exact[index * 3 + 2] - erodeCentroidZ;
+                            double dist = Math.sqrt(dx * dx + dz * dz);
+                            if (dist > erodeMaxDist) {
+                                erodeMaxDist = dist;
                             }
                         }
                     }
                 }
 
-                VectorMap<NativeBlockState>.Cursor stiltCursor = blocks.cursor();
-                while (stiltCursor.next()) {
-                    IrisBlockVector g = stiltCursor.key();
-                    NativeBlockState sourceData;
-                    try {
-                        sourceData = stiltCursor.value();
-                    } catch (Throwable e) {
-                        GenerationFailures.rethrowEngineFailure(e);
-                        IrisLogging.reportError(e);
-                        IrisLogging.warn("Failed to read block node " + g.getBlockX() + "," + g.getBlockY() + "," + g.getBlockZ() + " in object " + self.getLoadKey() + " (stilt cme)");
-                        sourceData = IrisObject.States.air();
-                    }
-
-                    if (sourceData == null) {
-                        IrisLogging.warn("Failed to read block node " + g.getBlockX() + "," + g.getBlockY() + "," + g.getBlockZ() + " in object " + self.getLoadKey() + " (stilt null)");
-                        sourceData = IrisObject.States.air();
-                    }
-
-                    if (!IrisObjectShaping.shouldStilt(sourceData, excludedStiltMaterials)) {
+                int targetLayer = ceilingHang ? topLayer : lowest;
+                for (int index = 0; index < count; index++) {
+                    int entry = bake.paletteIndex(index);
+                    if (!palette.shouldStilt(entry)) {
                         continue;
                     }
 
-                    NativeBlockState d = sourceData;
+                    NativeBlockState d;
                     if (settings != null && settings.getPalette() != null) {
                         d = config.getStiltSettings().getPalette().get(rng, x, y, z, rdata);
                     } else {
-                        String mat = IrisObjectShaping.materialKey(d);
-                        if (mat.equals("minecraft:grass_block") || mat.equals("minecraft:mycelium") || mat.equals("minecraft:podzol") || mat.equals("minecraft:dirt_path")) {
-                            d = IrisObject.States.dirt();
-                        }
+                        d = palette.stiltDefault(entry);
                     }
 
-                    IrisBlockVector i = g.clone();
-                    spin.rotate(i);
-                    if (ceilingHang) {
-                        i.setY(-i.getBlockY());
-                    }
-                    if (translating) {
-                        i.add(translateOffset);
-                    }
-                    int targetLayer = ceilingHang ? topLayer : lowest;
-                    if (i.getBlockY() != targetLayer)
+                    if (bake.layerY(index) != targetLayer)
                         continue;
-                    d = config.getRotation().rotate(d, spinx, spiny, spinz);
+                    d = palette.rotate(d);
 
                     if (hasEdits) {
+                        double exactX = exact[index * 3];
+                        double exactY = exact[index * 3 + 1];
+                        double exactZ = exact[index * 3 + 2];
                         for (IrisObjectReplace j : config.getEdit()) {
                             if (rng.chance(j.getChance())) {
                                 for (NativeBlockState k : j.getFind(rdata)) {
@@ -809,7 +693,7 @@ final class IrisObjectPlacementRunner {
                                         continue;
                                     }
                                     if (j.isExact() ? k.matches(d) : IrisObjectShaping.materialKey(k).equals(IrisObjectShaping.materialKey(d))) {
-                                        NativeBlockState newData = j.getReplace(rng, i.getX() + x, i.getY() + y, i.getZ() + z, rdata);
+                                        NativeBlockState newData = j.getReplace(rng, exactX + x, exactY + y, exactZ + z, rdata);
 
                                         if (IrisObjectShaping.materialKey(newData).equals(IrisObjectShaping.materialKey(d))) {
                                             d = BlockDataMergeSupport.merge(d, newData);
@@ -822,15 +706,18 @@ final class IrisObjectPlacementRunner {
                         }
                     }
 
-                    if (d == null || !IrisObjectShaping.shouldStilt(d, excludedStiltMaterials))
+                    if (d == null || !palette.shouldStiltPlaced(d))
                         continue;
 
-                    xx = x + (int) Math.round(i.getX());
-                    zz = z + (int) Math.round(i.getZ());
+                    xx = x + bake.offsetX(index);
+                    zz = z + bake.offsetZ(index);
 
                     if (warped) {
-                        xx += surfaceWarp.fitDouble(-warpHalf, warpHalf, i.getX() + x, i.getY() + y, i.getZ() + z);
-                        zz += surfaceWarp.fitDouble(-warpHalf, warpHalf, i.getZ() + z, i.getY() + y, i.getX() + x);
+                        double exactX = exact[index * 3];
+                        double exactY = exact[index * 3 + 1];
+                        double exactZ = exact[index * 3 + 2];
+                        xx += surfaceWarp.fitDouble(-warpHalf, warpHalf, exactX + x, exactY + y, exactZ + z);
+                        zz += surfaceWarp.fitDouble(-warpHalf, warpHalf, exactZ + z, exactY + y, exactX + x);
                     }
 
                     if (organic) {
@@ -891,8 +778,6 @@ final class IrisObjectPlacementRunner {
 
                     int highest = placer.getHighest(xx, zz, self.getLoader(), true);
 
-
-
                     int lowerBound = highest - 1;
                     if (settings != null) {
                         lowerBound -= config.getStiltSettings().getOverStilt() - rng.i(0, config.getStiltSettings().getYRand());
@@ -901,8 +786,8 @@ final class IrisObjectPlacementRunner {
                     }
 
                     if (eroding) {
-                        double dx = i.getX() - erodeCentroidX;
-                        double dz = i.getZ() - erodeCentroidZ;
+                        double dx = exact[index * 3] - erodeCentroidX;
+                        double dz = exact[index * 3 + 2] - erodeCentroidZ;
                         double normalizedDist = Math.sqrt(dx * dx + dz * dz) / erodeMaxDist;
                         normalizedDist = Math.min(normalizedDist, 1.0);
                         int totalDepth = (lowest + y) - lowerBound;
@@ -933,11 +818,10 @@ final class IrisObjectPlacementRunner {
                         }
                         placer.set(xx, j, zz, normalizePlacedWaterlogging(d, placer, xx, j, zz, waterlogCandidate));
                     }
-
                 }
-            } finally {
-                self.readLock.unlock();
             }
+        } finally {
+            self.readLock.unlock();
         }
 
         if (vacuuming && vacuumLowest != Integer.MAX_VALUE && placer.getEngine() != null) {
@@ -974,9 +858,76 @@ final class IrisObjectPlacementRunner {
         if (state == null || !IrisProceduralBlocks.hasProperty(state, "waterlogged")) {
             return state;
         }
+        if (!enabled && !"true".equals(IrisProceduralBlocks.propertyValue(state, "waterlogged"))) {
+            return IrisProceduralBlocks.normalizeWaterlogging(state, null, false);
+        }
         return IrisProceduralBlocks.normalizeWaterlogging(state, placer.get(x, y, z), enabled);
     }
 
+    private String[] resolveMarkers(IrisObjectPlacement config, RNG rng, int x, int yv, int z, IrisData rdata,
+                                    ObjectPlacementBake bake) {
+        self.readLock.lock();
+        try {
+            VectorMap<NativeBlockState> blocks = self.blocks;
+            KMap<IrisBlockVector, String> markers = new KMap<>();
+            KList<IrisBlockVector> list = StreamSupport.stream(blocks.keys().spliterator(), false)
+                    .collect(KList.collector());
+            // Marker selection persists into the mantle, so it must be seed-deterministic.
+            // Derive a side stream keyed on the placement position instead of consuming the
+            // caller's rng: consuming draws there would shift every later placement in the
+            // chunk and invalidate existing worlds/goldenhashes.
+            RNG markerRng = rng.nextParallelRNG(((((long) x) << 32) | (z & 0xFFFFFFFFL)) * 31L + yv);
+
+            int markerIndex = 0;
+            for (IrisObjectMarker j : config.getMarkers()) {
+                IrisMarker marker = self.getLoader().getMarkerLoader().load(j.getMarker());
+                int markerSalt = markerIndex++;
+
+                if (marker == null || marker.isCompatExcluded()) {
+                    continue;
+                }
+
+                int max = j.getMaximumMarkers();
+                for (IrisBlockVector i : list.shuffleCopy(markerRng.nextParallelRNG(markerSalt))) {
+                    if (max <= 0) {
+                        break;
+                    }
+
+                    NativeBlockState data = blocks.get(i);
+                    if (data == null) {
+                        continue;
+                    }
+
+                    for (NativeBlockState k : j.getMark(rdata)) {
+                        if (max <= 0) {
+                            break;
+                        }
+
+                        if (j.isExact() ? k.matches(data) : IrisObjectShaping.materialKey(k).equals(IrisObjectShaping.materialKey(data))) {
+                            boolean a = !blocks.containsKey((IrisBlockVector) i.clone().add(new IrisBlockVector(0, 1, 0)));
+                            boolean fff = !blocks.containsKey((IrisBlockVector) i.clone().add(new IrisBlockVector(0, 2, 0)));
+
+                            if (!marker.isEmptyAbove() || (a && fff)) {
+                                markers.put(i, j.getMarker());
+                                max--;
+                            }
+                        }
+                    }
+                }
+            }
+
+            String[] resolved = new String[bake.count()];
+            VectorMap<NativeBlockState>.Cursor cursor = blocks.cursor();
+            int index = 0;
+            while (index < resolved.length && cursor.next()) {
+                resolved[index++] = markers.get(cursor.key());
+            }
+            return resolved;
+        } finally {
+            self.readLock.unlock();
+        }
+    }
+
     private KList<IrisBlockVector> transformedPaintSupport(SpinKernel spin, IrisBlockVector translateOffset,
                                                           CNG warp, double half, int x, int y, int z) {
         KList<IrisBlockVector> offsets = new KList<>();
@@ -1337,152 +1288,159 @@ final class IrisObjectPlacementRunner {
         return result;
     }
 
-    /**
-     * Precomputed vector rotation for a single placement.
-     * <p>
-     * This mirrors {@link IrisObjectRotation#rotate(IrisBlockVector, int, int, int)} branch for branch, with two
-     * differences: it mutates the vector handed to it instead of cloning, and the per-axis angle plus its cosine
-     * and sine are resolved once instead of once per block. The angle is a pure function of the axis clamp and the
-     * spin, both fixed for the placement, and Math.cos/Math.sin are pure, so every produced double is identical to
-     * the value the per-call form would have produced.
-     */
-    private static final class SpinKernel {
-        private static final int MODE_NONE = 0;
-        private static final int MODE_FLIP = 1;
-        private static final int MODE_QUARTER = 2;
-        private static final int MODE_THREE_QUARTER = 3;
-        private static final int MODE_ANGLE = 4;
+    private record StateFacts(NativeBlockState rotated, boolean waterloggable, boolean authoredWaterlogged,
+                              NativeBlockState dry, boolean air) {
+        private static final StateFacts ROTATED_AWAY = new StateFacts(null, false, false, null, false);
+    }
 
-        private final boolean rotates;
-        private final int xMode;
-        private final int yMode;
-        private final int zMode;
-        private final double xCos;
-        private final double xSin;
-        private final double yCos;
-        private final double ySin;
-        private final double zCos;
-        private final double zSin;
+    private static final class PlacementStates {
+        private static final Object ROTATED_AWAY = new Object();
+        private static final byte UNKNOWN = 0;
+        private static final byte NO = 1;
+        private static final byte YES = 2;
 
-        private SpinKernel(IrisObjectRotation rotation, int spinx, int spiny, int spinz) {
-            rotates = rotation.canRotate();
-            xMode = rotation.canRotateX() ? modeOf(rotation.getXAxis()) : MODE_NONE;
-            zMode = rotation.canRotateZ() ? modeOf(rotation.getZAxis()) : MODE_NONE;
-            yMode = rotation.canRotateY() ? modeOf(rotation.getYAxis()) : MODE_NONE;
+        private final NativeBlockState[] palette;
+        private final IrisObjectRotation rotation;
+        private final int spinx;
+        private final int spiny;
+        private final int spinz;
+        private final boolean preventingDecay;
+        private final boolean debugSmartBore;
+        private final Set<String> excludedStiltMaterials;
+        private final NativeBlockState[] decayed;
+        private final StateFacts[] facts;
+        private final byte[] stiltLayers;
+        private final byte[] stilts;
+        private final NativeBlockState[] stiltDefaults;
+        private IdentityHashMap<NativeBlockState, Object> rotations;
+        private IdentityHashMap<NativeBlockState, StateFacts> editedFacts;
+        private IdentityHashMap<NativeBlockState, Boolean> placedStilts;
 
-            double xAngle = xMode == MODE_ANGLE ? rotation.getXRotation(spinx) : 0;
-            double zAngle = zMode == MODE_ANGLE ? rotation.getZRotation(spinz) : 0;
-            double yAngle = yMode == MODE_ANGLE ? rotation.getYRotation(spiny) : 0;
-            xCos = Math.cos(xAngle);
-            xSin = Math.sin(xAngle);
-            zCos = Math.cos(zAngle);
-            zSin = Math.sin(zAngle);
-            yCos = Math.cos(yAngle);
-            ySin = Math.sin(yAngle);
+        private PlacementStates(NativeBlockState[] palette, IrisObjectRotation rotation, int spinx, int spiny, int spinz,
+                                boolean preventingDecay, boolean debugSmartBore, Set<String> excludedStiltMaterials) {
+            this.palette = palette;
+            this.rotation = rotation;
+            this.spinx = spinx;
+            this.spiny = spiny;
+            this.spinz = spinz;
+            this.preventingDecay = preventingDecay;
+            this.debugSmartBore = debugSmartBore;
+            this.excludedStiltMaterials = excludedStiltMaterials;
+            this.decayed = new NativeBlockState[palette.length];
+            this.facts = new StateFacts[palette.length];
+            this.stiltLayers = new byte[palette.length];
+            this.stilts = new byte[palette.length];
+            this.stiltDefaults = new NativeBlockState[palette.length];
         }
 
-        private static int modeOf(IrisAxisRotationClamp clamp) {
-            if (!clamp.isLocked()) {
-                return MODE_ANGLE;
-            }
-
-            if (Math.abs(clamp.getMax()) % 360D == 180D) {
-                return MODE_FLIP;
-            }
-
-            if (clamp.getMax() % 360D == 90D || clamp.getMax() % 360D == -270D) {
-                return MODE_QUARTER;
-            }
-
-            if (clamp.getMax() == -90D || clamp.getMax() % 360D == 270D) {
-                return MODE_THREE_QUARTER;
-            }
-
-            return MODE_ANGLE;
+        private NativeBlockState source(int entry) {
+            NativeBlockState state = palette[entry];
+            return debugSmartBore && IrisObject.States.vair().equals(state) ? IrisObject.States.vairDebug() : state;
         }
 
-        /**
-         * Rotates in place. Axis order (X, then Z, then Y) is load bearing.
-         */
-        private void rotate(IrisBlockVector v) {
-            if (!rotates) {
-                return;
+        private boolean stiltLayer(int entry) {
+            byte known = stiltLayers[entry];
+            if (known == UNKNOWN) {
+                known = IrisObjectShaping.isStiltLayerBlock(source(entry)) ? YES : NO;
+                stiltLayers[entry] = known;
             }
+            return known == YES;
+        }
 
-            switch (xMode) {
-                case MODE_FLIP -> {
-                    v.setZ(-v.getZ());
-                    v.setY(-v.getY());
-                }
-                case MODE_QUARTER -> {
-                    double z = v.getZ();
-                    v.setZ(v.getY());
-                    v.setY(-z);
-                }
-                case MODE_THREE_QUARTER -> {
-                    double z = v.getZ();
-                    v.setZ(-v.getY());
-                    v.setY(z);
-                }
-                case MODE_ANGLE -> {
-                    double y = xCos * v.getY() - xSin * v.getZ();
-                    double z = xSin * v.getY() + xCos * v.getZ();
-                    v.setY(y);
-                    v.setZ(z);
-                }
-                default -> {
-                }
+        private NativeBlockState decayed(int entry) {
+            NativeBlockState resolved = decayed[entry];
+            if (resolved == null) {
+                NativeBlockState data = source(entry);
+                resolved = preventingDecay && IrisProceduralBlocks.hasProperty(data, "distance")
+                        && "false".equals(IrisProceduralBlocks.propertyValue(data, "persistent"))
+                        ? data.withProperty("persistent", "true") : data;
+                decayed[entry] = resolved;
             }
+            return resolved;
+        }
 
-            switch (zMode) {
-                case MODE_FLIP -> {
-                    v.setY(-v.getY());
-                    v.setX(-v.getX());
-                }
-                case MODE_QUARTER -> {
-                    double y = v.getY();
-                    v.setY(v.getX());
-                    v.setX(-y);
-                }
-                case MODE_THREE_QUARTER -> {
-                    double y = v.getY();
-                    v.setY(-v.getX());
-                    v.setX(y);
-                }
-                case MODE_ANGLE -> {
-                    double x = zCos * v.getX() - zSin * v.getY();
-                    double y = zSin * v.getX() + zCos * v.getY();
-                    v.setX(x);
-                    v.setY(y);
-                }
-                default -> {
-                }
+        private StateFacts facts(int entry) {
+            StateFacts resolved = facts[entry];
+            if (resolved == null) {
+                resolved = computeFacts(decayed(entry));
+                facts[entry] = resolved;
             }
+            return resolved;
+        }
 
-            switch (yMode) {
-                case MODE_FLIP -> {
-                    v.setX(-v.getX());
-                    v.setZ(-v.getZ());
-                }
-                case MODE_QUARTER -> {
-                    double x = v.getX();
-                    v.setX(v.getZ());
-                    v.setZ(-x);
-                }
-                case MODE_THREE_QUARTER -> {
-                    double x = v.getX();
-                    v.setX(-v.getZ());
-                    v.setZ(x);
-                }
-                case MODE_ANGLE -> {
-                    double x = yCos * v.getX() + ySin * v.getZ();
-                    double z = -ySin * v.getX() + yCos * v.getZ();
-                    v.setX(x);
-                    v.setZ(z);
-                }
-                default -> {
-                }
+        private StateFacts factsOf(NativeBlockState state) {
+            if (editedFacts == null) {
+                editedFacts = new IdentityHashMap<>();
             }
+            StateFacts resolved = editedFacts.get(state);
+            if (resolved == null) {
+                resolved = computeFacts(state);
+                editedFacts.put(state, resolved);
+            }
+            return resolved;
+        }
+
+        private StateFacts computeFacts(NativeBlockState state) {
+            NativeBlockState rotated = rotate(state);
+            if (rotated == null) {
+                return StateFacts.ROTATED_AWAY;
+            }
+            boolean waterloggable = IrisProceduralBlocks.hasProperty(rotated, "waterlogged");
+            boolean authored = waterloggable && "true".equals(IrisProceduralBlocks.propertyValue(rotated, "waterlogged"));
+            NativeBlockState dry = waterloggable ? IrisProceduralBlocks.normalizeWaterlogging(rotated, null, false) : rotated;
+            String material = IrisObjectShaping.materialKey(rotated);
+            boolean air = material.equals("minecraft:air") || material.equals("minecraft:cave_air");
+            return new StateFacts(rotated, waterloggable, authored, dry, air);
+        }
+
+        private NativeBlockState rotate(NativeBlockState state) {
+            if (state == null) {
+                return null;
+            }
+            if (rotations == null) {
+                rotations = new IdentityHashMap<>();
+            }
+            Object memo = rotations.get(state);
+            if (memo == null) {
+                NativeBlockState rotated = rotation.rotate(state, spinx, spiny, spinz);
+                memo = rotated == null ? ROTATED_AWAY : rotated;
+                rotations.put(state, memo);
+            }
+            return memo == ROTATED_AWAY ? null : (NativeBlockState) memo;
+        }
+
+        private boolean shouldStilt(int entry) {
+            byte known = stilts[entry];
+            if (known == UNKNOWN) {
+                known = IrisObjectShaping.shouldStilt(palette[entry], excludedStiltMaterials) ? YES : NO;
+                stilts[entry] = known;
+            }
+            return known == YES;
+        }
+
+        private NativeBlockState stiltDefault(int entry) {
+            NativeBlockState resolved = stiltDefaults[entry];
+            if (resolved == null) {
+                NativeBlockState state = palette[entry];
+                String material = IrisObjectShaping.materialKey(state);
+                resolved = material.equals("minecraft:grass_block") || material.equals("minecraft:mycelium")
+                        || material.equals("minecraft:podzol") || material.equals("minecraft:dirt_path")
+                        ? IrisObject.States.dirt() : state;
+                stiltDefaults[entry] = resolved;
+            }
+            return resolved;
+        }
+
+        private boolean shouldStiltPlaced(NativeBlockState state) {
+            if (placedStilts == null) {
+                placedStilts = new IdentityHashMap<>();
+            }
+            Boolean known = placedStilts.get(state);
+            if (known == null) {
+                known = IrisObjectShaping.shouldStilt(state, excludedStiltMaterials);
+                placedStilts.put(state, known);
+            }
+            return known;
         }
     }
 
diff --git a/core/src/main/java/art/arcane/iris/structure/object/ObjectPlacementBake.java b/core/src/main/java/art/arcane/iris/structure/object/ObjectPlacementBake.java
new file mode 100644
index 000000000..58470a119
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/structure/object/ObjectPlacementBake.java
@@ -0,0 +1,259 @@
+package art.arcane.iris.structure.object;
+
+import art.arcane.iris.generation.block.TileData;
+import art.arcane.iris.generation.block.VectorMap;
+import art.arcane.iris.generation.decoration.tree.TreeGrounding;
+import art.arcane.iris.generation.geometry.IrisBlockVector;
+import art.arcane.volmlib.nativelib.terrain.NativeBlockState;
+import it.unimi.dsi.fastutil.ints.IntArrayList;
+
+import java.util.ArrayList;
+import java.util.IdentityHashMap;
+import java.util.List;
+import java.util.concurrent.ConcurrentHashMap;
+
+final class ObjectPlacementBake {
+    private static final int MAXIMUM_VARIANTS_PER_OBJECT = 32;
+
+    private final long blocksRevision;
+    private final long statesRevision;
+    private final TreeGrounding grounding;
+    private final int count;
+    private final int[] offsetX;
+    private final int[] offsetY;
+    private final int[] offsetZ;
+    private final int[] layerY;
+    private final short[] paletteIndexes;
+    private final NativeBlockState[] palette;
+    private final int[] tileBlocks;
+    private final TileData[] tileValues;
+    private final long[] canopy;
+    private final Key key;
+    private volatile double[] exact;
+
+    private ObjectPlacementBake(Key key, long blocksRevision, long statesRevision, TreeGrounding grounding, int count,
+                                int[] offsetX, int[] offsetY, int[] offsetZ, int[] layerY, short[] paletteIndexes,
+                                NativeBlockState[] palette, int[] tileBlocks, TileData[] tileValues, long[] canopy) {
+        this.key = key;
+        this.blocksRevision = blocksRevision;
+        this.statesRevision = statesRevision;
+        this.grounding = grounding;
+        this.count = count;
+        this.offsetX = offsetX;
+        this.offsetY = offsetY;
+        this.offsetZ = offsetZ;
+        this.layerY = layerY;
+        this.paletteIndexes = paletteIndexes;
+        this.palette = palette;
+        this.tileBlocks = tileBlocks;
+        this.tileValues = tileValues;
+        this.canopy = canopy;
+    }
+
+    static ObjectPlacementBake of(IrisObject object, SpinKernel spin, boolean ceilingHang, IrisBlockVector translateOffset) {
+        Key key = Key.of(spin, ceilingHang, translateOffset);
+        ConcurrentHashMap<Key, ObjectPlacementBake> variants = object.placementBakes;
+        ObjectPlacementBake cached = variants.get(key);
+        if (cached != null && cached.matches(object)) {
+            return cached;
+        }
+        ObjectPlacementBake built = bake(object, key, spin, ceilingHang, translateOffset);
+        if (built.matches(object)) {
+            if (variants.size() >= MAXIMUM_VARIANTS_PER_OBJECT) {
+                variants.clear();
+            }
+            variants.put(key, built);
+        }
+        return built;
+    }
+
+    private static ObjectPlacementBake bake(IrisObject object, Key key, SpinKernel spin, boolean ceilingHang,
+                                            IrisBlockVector translateOffset) {
+        object.readLock.lock();
+        try {
+            VectorMap<NativeBlockState> blocks = object.blocks;
+            VectorMap<TileData> states = object.states;
+            long blocksRevision = blocks.modificationRevision();
+            long statesRevision = states.modificationRevision();
+            TreeGrounding grounding = object.getTreeGrounding();
+            boolean hasStates = !states.isEmpty();
+            IntArrayList x = new IntArrayList();
+            IntArrayList y = new IntArrayList();
+            IntArrayList z = new IntArrayList();
+            IntArrayList layer = new IntArrayList();
+            IntArrayList indexes = new IntArrayList();
+            IntArrayList tileBlocks = new IntArrayList();
+            List<TileData> tileValues = new ArrayList<>();
+            List<NativeBlockState> palette = new ArrayList<>();
+            IdentityHashMap<NativeBlockState, Integer> paletteSlots = new IdentityHashMap<>();
+            IntArrayList canopyBlocks = new IntArrayList();
+            boolean layerDiffers = false;
+            IrisBlockVector rotated = new IrisBlockVector(0, 0, 0);
+            VectorMap<NativeBlockState>.Cursor cursor = blocks.cursor();
+            int index = 0;
+            while (cursor.next()) {
+                IrisBlockVector source = cursor.key();
+                NativeBlockState state = cursor.value();
+                if (state == null) {
+                    state = IrisObject.States.air();
+                }
+                transform(source, rotated, spin, ceilingHang, translateOffset);
+                int roundedY = (int) Math.round(rotated.getY());
+                int floorY = rotated.getBlockY();
+                x.add((int) Math.round(rotated.getX()));
+                y.add(roundedY);
+                z.add((int) Math.round(rotated.getZ()));
+                layer.add(floorY);
+                layerDiffers |= floorY != roundedY;
+                Integer slot = paletteSlots.get(state);
+                if (slot == null) {
+                    slot = palette.size();
+                    palette.add(state);
+                    paletteSlots.put(state, slot);
+                }
+                indexes.add(slot);
+                if (hasStates) {
+                    TileData tile = states.get(source);
+                    if (tile != null) {
+                        tileBlocks.add(index);
+                        tileValues.add(tile);
+                    }
+                }
+                if (grounding != null && grounding.isCanopy(source.getBlockX(), source.getBlockY(), source.getBlockZ())) {
+                    canopyBlocks.add(index);
+                }
+                index++;
+            }
+            if (palette.size() > Short.MAX_VALUE) {
+                throw new IllegalStateException("Object " + object.getLoadKey() + " has more than "
+                        + Short.MAX_VALUE + " distinct block states");
+            }
+            short[] paletteIndexes = new short[index];
+            for (int block = 0; block < index; block++) {
+                paletteIndexes[block] = (short) indexes.getInt(block);
+            }
+            long[] canopy = null;
+            if (!canopyBlocks.isEmpty()) {
+                canopy = new long[(index + 63) >>> 6];
+                for (int block : canopyBlocks) {
+                    canopy[block >>> 6] |= 1L << (block & 63);
+                }
+            }
+            return new ObjectPlacementBake(key, blocksRevision, statesRevision, grounding, index,
+                    x.toIntArray(), y.toIntArray(), z.toIntArray(), layerDiffers ? layer.toIntArray() : null,
+                    paletteIndexes, palette.toArray(new NativeBlockState[0]),
+                    tileBlocks.isEmpty() ? null : tileBlocks.toIntArray(),
+                    tileValues.isEmpty() ? null : tileValues.toArray(new TileData[0]), canopy);
+        } finally {
+            object.readLock.unlock();
+        }
+    }
+
+    private static void transform(IrisBlockVector source, IrisBlockVector target, SpinKernel spin, boolean ceilingHang,
+                                  IrisBlockVector translateOffset) {
+        target.setX(source.getX());
+        target.setY(source.getY());
+        target.setZ(source.getZ());
+        spin.rotate(target);
+        if (ceilingHang) {
+            target.setY(-target.getBlockY());
+        }
+        if (translateOffset != null) {
+            target.add(translateOffset);
+        }
+    }
+
+    boolean matches(IrisObject object) {
+        return object.blocks.modificationRevision() == blocksRevision
+                && object.states.modificationRevision() == statesRevision
+                && object.getTreeGrounding() == grounding;
+    }
+
+    int count() {
+        return count;
+    }
+
+    int offsetX(int index) {
+        return offsetX[index];
+    }
+
+    int offsetY(int index) {
+        return offsetY[index];
+    }
+
+    int offsetZ(int index) {
+        return offsetZ[index];
+    }
+
+    int layerY(int index) {
+        return layerY == null ? offsetY[index] : layerY[index];
+    }
+
+    int paletteIndex(int index) {
+        return paletteIndexes[index];
+    }
+
+    NativeBlockState[] palette() {
+        return palette;
+    }
+
+    int[] tileBlocks() {
+        return tileBlocks;
+    }
+
+    TileData[] tileValues() {
+        return tileValues;
+    }
+
+    boolean canopy(int index) {
+        return canopy != null && (canopy[index >>> 6] & (1L << (index & 63))) != 0L;
+    }
+
+    double[] exact(IrisObject object, SpinKernel spin) {
+        double[] resolved = exact;
+        if (resolved != null) {
+            return resolved;
+        }
+        object.readLock.lock();
+        try {
+            resolved = new double[count * 3];
+            IrisBlockVector rotated = new IrisBlockVector(0, 0, 0);
+            VectorMap<NativeBlockState>.Cursor cursor = object.blocks.cursor();
+            int index = 0;
+            while (cursor.next() && index < count) {
+                transform(cursor.key(), rotated, spin, key.ceilingHang(), key.translateOffset());
+                resolved[index * 3] = rotated.getX();
+                resolved[index * 3 + 1] = rotated.getY();
+                resolved[index * 3 + 2] = rotated.getZ();
+                index++;
+            }
+            if (index != count) {
+                throw new IllegalStateException("Object " + object.getLoadKey() + " changed while its placement bake was read");
+            }
+        } finally {
+            object.readLock.unlock();
+        }
+        exact = resolved;
+        return resolved;
+    }
+
+    record Key(boolean rotates, int xMode, int yMode, int zMode, long xCos, long xSin, long yCos, long ySin,
+               long zCos, long zSin, boolean ceilingHang, boolean translating, long translateX, long translateY,
+               long translateZ) {
+        static Key of(SpinKernel spin, boolean ceilingHang, IrisBlockVector translateOffset) {
+            boolean translating = translateOffset != null;
+            return new Key(spin.rotates, spin.xMode, spin.yMode, spin.zMode,
+                    Double.doubleToLongBits(spin.xCos), Double.doubleToLongBits(spin.xSin),
+                    Double.doubleToLongBits(spin.yCos), Double.doubleToLongBits(spin.ySin),
+                    Double.doubleToLongBits(spin.zCos), Double.doubleToLongBits(spin.zSin), ceilingHang, translating,
+                    translating ? Double.doubleToLongBits(translateOffset.getX()) : 0L,
+                    translating ? Double.doubleToLongBits(translateOffset.getY()) : 0L,
+                    translating ? Double.doubleToLongBits(translateOffset.getZ()) : 0L);
+        }
+
+        IrisBlockVector translateOffset() {
+            return translating ? new IrisBlockVector(Double.longBitsToDouble(translateX),
+                    Double.longBitsToDouble(translateY), Double.longBitsToDouble(translateZ)) : null;
+        }
+    }
+}
diff --git a/core/src/main/java/art/arcane/iris/structure/object/SpinKernel.java b/core/src/main/java/art/arcane/iris/structure/object/SpinKernel.java
new file mode 100644
index 000000000..abaa1598c
--- /dev/null
+++ b/core/src/main/java/art/arcane/iris/structure/object/SpinKernel.java
@@ -0,0 +1,152 @@
+package art.arcane.iris.structure.object;
+
+import art.arcane.iris.generation.geometry.IrisBlockVector;
+
+/**
+ * Precomputed vector rotation for a single placement.
+ * <p>
+ * This mirrors {@link IrisObjectRotation#rotate(IrisBlockVector, int, int, int)} branch for branch, with two
+ * differences: it mutates the vector handed to it instead of cloning, and the per-axis angle plus its cosine
+ * and sine are resolved once instead of once per block. The angle is a pure function of the axis clamp and the
+ * spin, both fixed for the placement, and Math.cos/Math.sin are pure, so every produced double is identical to
+ * the value the per-call form would have produced.
+ */
+final class SpinKernel {
+    static final int MODE_NONE = 0;
+    static final int MODE_FLIP = 1;
+    static final int MODE_QUARTER = 2;
+    static final int MODE_THREE_QUARTER = 3;
+    static final int MODE_ANGLE = 4;
+
+    final boolean rotates;
+    final int xMode;
+    final int yMode;
+    final int zMode;
+    final double xCos;
+    final double xSin;
+    final double yCos;
+    final double ySin;
+    final double zCos;
+    final double zSin;
+
+    SpinKernel(IrisObjectRotation rotation, int spinx, int spiny, int spinz) {
+        rotates = rotation.canRotate();
+        xMode = rotation.canRotateX() ? modeOf(rotation.getXAxis()) : MODE_NONE;
+        zMode = rotation.canRotateZ() ? modeOf(rotation.getZAxis()) : MODE_NONE;
+        yMode = rotation.canRotateY() ? modeOf(rotation.getYAxis()) : MODE_NONE;
+
+        double xAngle = xMode == MODE_ANGLE ? rotation.getXRotation(spinx) : 0;
+        double zAngle = zMode == MODE_ANGLE ? rotation.getZRotation(spinz) : 0;
+        double yAngle = yMode == MODE_ANGLE ? rotation.getYRotation(spiny) : 0;
+        xCos = Math.cos(xAngle);
+        xSin = Math.sin(xAngle);
+        zCos = Math.cos(zAngle);
+        zSin = Math.sin(zAngle);
+        yCos = Math.cos(yAngle);
+        ySin = Math.sin(yAngle);
+    }
+
+    private static int modeOf(IrisAxisRotationClamp clamp) {
+        if (!clamp.isLocked()) {
+            return MODE_ANGLE;
+        }
+
+        if (Math.abs(clamp.getMax()) % 360D == 180D) {
+            return MODE_FLIP;
+        }
+
+        if (clamp.getMax() % 360D == 90D || clamp.getMax() % 360D == -270D) {
+            return MODE_QUARTER;
+        }
+
+        if (clamp.getMax() == -90D || clamp.getMax() % 360D == 270D) {
+            return MODE_THREE_QUARTER;
+        }
+
+        return MODE_ANGLE;
+    }
+
+    /**
+     * Rotates in place. Axis order (X, then Z, then Y) is load bearing.
+     */
+    void rotate(IrisBlockVector v) {
+        if (!rotates) {
+            return;
+        }
+
+        switch (xMode) {
+            case MODE_FLIP -> {
+                v.setZ(-v.getZ());
+                v.setY(-v.getY());
+            }
+            case MODE_QUARTER -> {
+                double z = v.getZ();
+                v.setZ(v.getY());
+                v.setY(-z);
+            }
+            case MODE_THREE_QUARTER -> {
+                double z = v.getZ();
+                v.setZ(-v.getY());
+                v.setY(z);
+            }
+            case MODE_ANGLE -> {
+                double y = xCos * v.getY() - xSin * v.getZ();
+                double z = xSin * v.getY() + xCos * v.getZ();
+                v.setY(y);
+                v.setZ(z);
+            }
+            default -> {
+            }
+        }
+
+        switch (zMode) {
+            case MODE_FLIP -> {
+                v.setY(-v.getY());
+                v.setX(-v.getX());
+            }
+            case MODE_QUARTER -> {
+                double y = v.getY();
+                v.setY(v.getX());
+                v.setX(-y);
+            }
+            case MODE_THREE_QUARTER -> {
+                double y = v.getY();
+                v.setY(-v.getX());
+                v.setX(y);
+            }
+            case MODE_ANGLE -> {
+                double x = zCos * v.getX() - zSin * v.getY();
+                double y = zSin * v.getX() + zCos * v.getY();
+                v.setX(x);
+                v.setY(y);
+            }
+            default -> {
+            }
+        }
+
+        switch (yMode) {
+            case MODE_FLIP -> {
+                v.setX(-v.getX());
+                v.setZ(-v.getZ());
+            }
+            case MODE_QUARTER -> {
+                double x = v.getX();
+                v.setX(v.getZ());
+                v.setZ(-x);
+            }
+            case MODE_THREE_QUARTER -> {
+                double x = v.getX();
+                v.setX(-v.getZ());
+                v.setZ(x);
+            }
+            case MODE_ANGLE -> {
+                double x = yCos * v.getX() + ySin * v.getZ();
+                double z = -ySin * v.getX() + yCos * v.getZ();
+                v.setX(x);
+                v.setZ(z);
+            }
+            default -> {
+            }
+        }
+    }
+}
diff --git a/core/src/test/java/art/arcane/iris/generation/mantle/MutationLogTest.java b/core/src/test/java/art/arcane/iris/generation/mantle/MutationLogTest.java
new file mode 100644
index 000000000..9a47e059d
--- /dev/null
+++ b/core/src/test/java/art/arcane/iris/generation/mantle/MutationLogTest.java
@@ -0,0 +1,81 @@
+package art.arcane.iris.generation.mantle;
+
+import art.arcane.iris.testsupport.KeyedBlockState;
+import art.arcane.volmlib.nativelib.terrain.NativeBlockState;
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertThrows;
+import static org.junit.Assert.assertTrue;
+
+public class MutationLogTest {
+    @Test
+    public void logKeepsPositionsValuesAndFlagsInOrder() {
+        NativeBlockState state = new KeyedBlockState("minecraft:stone");
+        MutationLog log = MutationLog.of(List.of(
+                new ObjectDestinationTransaction.SetMutation(new ObjectDestinationTransaction.DataKey(3, 70, -2, String.class), "marker", true),
+                new ObjectDestinationTransaction.CustomBlockMutation(new ObjectDestinationTransaction.DataKey(-17, 4, 40, NativeBlockState.class), state, false)));
+        for (int index = 0; index < 100; index++) {
+            log.add(index, index + 1, -index, "grow" + index, (index & 1) == 0, (index & 2) == 0);
+        }
+
+        assertEquals(102, log.size());
+        assertEquals(3, log.x(0));
+        assertEquals(70, log.y(0));
+        assertEquals(-2, log.z(0));
+        assertEquals("marker", log.value(0));
+        assertFalse(log.custom(0));
+        assertTrue(log.canopy(0));
+        assertSame(String.class, log.type(0));
+        assertSame(state, log.value(1));
+        assertTrue(log.custom(1));
+        assertFalse(log.canopy(1));
+        assertSame(NativeBlockState.class, log.type(1));
+        assertEquals(99, log.x(101));
+        assertEquals("grow99", log.value(101));
+        assertFalse(log.custom(101));
+        assertTrue(log.canopy(98));
+        assertFalse(log.canopy(100));
+    }
+
+    @Test
+    public void mismatchedMutationTypesAreRejected() {
+        assertThrows(IllegalArgumentException.class, () -> MutationLog.of(List.of(
+                new ObjectDestinationTransaction.SetMutation(new ObjectDestinationTransaction.DataKey(0, 4, 0, Integer.class), "text", false))));
+    }
+
+    @Test
+    public void planSlicesMatchThePlanBuiltFromTheSameMutations() {
+        MutationLog log = new MutationLog();
+        List<ObjectDestinationTransaction.Mutation> tail = new ArrayList<>();
+        for (int index = 0; index < 64; index++) {
+            int x = (index * 7) - 30;
+            int y = 4 + index;
+            int z = (index * 5) - 20;
+            String value = "value" + (index % 9);
+            boolean canopy = index % 4 == 0;
+            log.add(x, y, z, value, false, canopy);
+            if (index >= 10) {
+                tail.add(new ObjectDestinationTransaction.SetMutation(new ObjectDestinationTransaction.DataKey(x, y, z, String.class), value, canopy));
+            }
+        }
+        ObjectSourcePlan sliced = new ObjectSourcePlan(log, 10, List.of());
+        ObjectSourcePlan expected = new ObjectSourcePlan(tail);
+
+        assertEquals(expected.destinationCount(), sliced.destinationCount());
+        int total = 0;
+        for (int chunkX = -3; chunkX <= 30; chunkX++) {
+            for (int chunkZ = -3; chunkZ <= 30; chunkZ++) {
+                List<ObjectDestinationTransaction.Mutation> mutations = sliced.mutationsFor(chunkX, chunkZ);
+                assertEquals(expected.mutationsFor(chunkX, chunkZ), mutations);
+                total += mutations.size();
+            }
+        }
+        assertEquals(54, total);
+    }
+}
diff --git a/core/src/test/java/art/arcane/iris/generation/mantle/ObjectSourcePlanCacheTest.java b/core/src/test/java/art/arcane/iris/generation/mantle/ObjectSourcePlanCacheTest.java
index 25d05d0b2..9c88b387e 100644
--- a/core/src/test/java/art/arcane/iris/generation/mantle/ObjectSourcePlanCacheTest.java
+++ b/core/src/test/java/art/arcane/iris/generation/mantle/ObjectSourcePlanCacheTest.java
@@ -163,6 +163,44 @@ public class ObjectSourcePlanCacheTest {
         }
     }
 
+    @Test
+    public void tryAcquireReportsBusySourcesWithoutConsumingThem() throws Exception {
+        ObjectSourcePlanCache cache = new ObjectSourcePlanCache(1024L * 1024L);
+        ObjectSourcePlan plan = planTouching(new int[]{0, 0}, new int[]{1, 0});
+        CountDownLatch entered = new CountDownLatch(1);
+        CountDownLatch release = new CountDownLatch(1);
+        AtomicInteger builds = new AtomicInteger();
+        ExecutorService executor = Executors.newFixedThreadPool(1);
+        try {
+            Future<ObjectSourcePlan> owner = executor.submit(() -> cache.acquire(0, 0, 0, 0, 7, () -> {
+                builds.incrementAndGet();
+                entered.countDown();
+                await(release);
+                return plan;
+            }));
+            assertTrue(entered.await(5L, TimeUnit.SECONDS));
+
+            assertSame(ObjectSourcePlanCache.BUSY, cache.tryAcquire(0, 0, 1, 0, 7, () -> {
+                builds.incrementAndGet();
+                return plan;
+            }));
+            ObjectSourcePlan unrelated = planTouching(new int[]{5, 5});
+            assertSame(unrelated, cache.tryAcquire(5, 5, 5, 5, 7, () -> unrelated));
+            release.countDown();
+            assertSame(plan, owner.get(5L, TimeUnit.SECONDS));
+
+            assertSame(plan, cache.tryAcquire(0, 0, 1, 0, 7, () -> {
+                builds.incrementAndGet();
+                return plan;
+            }));
+            assertEquals(1, builds.get());
+            assertEquals(2L, cache.stats().drained());
+        } finally {
+            release.countDown();
+            executor.shutdownNow();
+        }
+    }
+
     @Test
     public void concurrentDestinationsShareOneSourceBuild() throws Exception {
         ObjectSourcePlanCache cache = new ObjectSourcePlanCache(1024L * 1024L);
diff --git a/core/src/test/java/art/arcane/iris/generation/noise/GeneratorProgramParityTest.java b/core/src/test/java/art/arcane/iris/generation/noise/GeneratorProgramParityTest.java
new file mode 100644
index 000000000..016d1c6cb
--- /dev/null
+++ b/core/src/test/java/art/arcane/iris/generation/noise/GeneratorProgramParityTest.java
@@ -0,0 +1,160 @@
+package art.arcane.iris.generation.noise;
+
+import art.arcane.volmlib.util.collection.KList;
+import org.junit.Test;
+
+import java.util.SplittableRandom;
+
+import static org.junit.Assert.assertEquals;
+
+public class GeneratorProgramParityTest {
+    private static final NoiseStyle[] STYLES = {
+            NoiseStyle.SIMPLEX, NoiseStyle.PERLIN, NoiseStyle.IRIS, NoiseStyle.IRIS_HALF, NoiseStyle.FRACTAL_SMOKE,
+            NoiseStyle.FRACTAL_WATER, NoiseStyle.CLOVER, NoiseStyle.CELLULAR, NoiseStyle.NOWHERE,
+            NoiseStyle.CELLULAR_IRIS_DOUBLE, NoiseStyle.SIMPLEX_VASCULAR, NoiseStyle.FLAT, NoiseStyle.STATIC,
+            NoiseStyle.GLOB_IRIS_THICK, NoiseStyle.FRACTAL_BILLOW_PERLIN, NoiseStyle.PERLIN_IRIS
+    };
+
+    @Test
+    public void programHeightsMatchScalarHeightsBitForBit() {
+        SplittableRandom random = new SplittableRandom(0x5EED1E55L);
+        TerrainBatchScratch scratch = new TerrainBatchScratch();
+        for (int generatorIndex = 0; generatorIndex < 160; generatorIndex++) {
+            long shapeSeed = random.nextLong();
+            IrisGenerator scalar = generator(new SplittableRandom(shapeSeed));
+            IrisGenerator batch = generator(new SplittableRandom(shapeSeed));
+            long superSeed = random.nextLong();
+            GeneratorProgram program = batch.compileProgram(superSeed);
+            int count = 1 + random.nextInt(600);
+            double[] xs = new double[count];
+            double[] zs = new double[count];
+            double[] out = new double[count];
+            fillCoordinates(random, xs, zs, count);
+            program.heights(scratch, xs, zs, count, out);
+            for (int index = 0; index < count; index++) {
+                assertEquals("generator " + generatorIndex + " point " + xs[index] + "," + zs[index],
+                        Double.doubleToRawLongBits(scalar.getHeight(xs[index], zs[index], superSeed)),
+                        Double.doubleToRawLongBits(out[index]));
+            }
+        }
+    }
+
+    @Test
+    public void singlePointProgramHeightsMatchScalarHeightsBitForBit() {
+        SplittableRandom random = new SplittableRandom(0xFEEDL);
+        TerrainBatchScratch scratch = new TerrainBatchScratch();
+        for (int generatorIndex = 0; generatorIndex < 160; generatorIndex++) {
+            long shapeSeed = random.nextLong();
+            IrisGenerator scalar = generator(new SplittableRandom(shapeSeed));
+            IrisGenerator compiled = generator(new SplittableRandom(shapeSeed));
+            long superSeed = random.nextLong();
+            GeneratorProgram program = compiled.compileProgram(superSeed);
+            for (int sample = 0; sample < 400; sample++) {
+                double x = coordinate(random);
+                double z = random.nextInt(5) == 0 ? x : coordinate(random);
+                assertEquals("generator " + generatorIndex + " point " + x + "," + z,
+                        Double.doubleToRawLongBits(scalar.getHeight(x, z, superSeed)),
+                        Double.doubleToRawLongBits(program.height(scratch, x, z)));
+            }
+        }
+    }
+
+    @Test
+    public void chunkGridsMatchScalarHeightsBitForBit() {
+        SplittableRandom random = new SplittableRandom(0xC0FFEEL);
+        TerrainBatchScratch scratch = new TerrainBatchScratch();
+        double[] xs = new double[256];
+        double[] zs = new double[256];
+        double[] out = new double[256];
+        for (int generatorIndex = 0; generatorIndex < 60; generatorIndex++) {
+            long shapeSeed = random.nextLong();
+            IrisGenerator scalar = generator(new SplittableRandom(shapeSeed));
+            IrisGenerator batch = generator(new SplittableRandom(shapeSeed));
+            long superSeed = random.nextLong();
+            GeneratorProgram program = batch.compileProgram(superSeed);
+            for (int chunk = 0; chunk < 4; chunk++) {
+                int originX = random.nextInt(-200_000, 200_000) << 4;
+                int originZ = random.nextInt(-200_000, 200_000) << 4;
+                for (int index = 0; index < 256; index++) {
+                    xs[index] = originX + (index & 15);
+                    zs[index] = originZ + (index >> 4);
+                }
+                program.heights(scratch, xs, zs, 256, out);
+                for (int index = 0; index < 256; index++) {
+                    assertEquals(Double.doubleToRawLongBits(scalar.getHeight(xs[index], zs[index], superSeed)),
+                            Double.doubleToRawLongBits(out[index]));
+                }
+            }
+        }
+    }
+
+    private static void fillCoordinates(SplittableRandom random, double[] xs, double[] zs, int count) {
+        for (int index = 0; index < count; index++) {
+            xs[index] = coordinate(random);
+            zs[index] = random.nextInt(5) == 0 ? xs[index] : coordinate(random);
+        }
+    }
+
+    private static double coordinate(SplittableRandom random) {
+        return switch (random.nextInt(6)) {
+            case 0 -> random.nextInt(-4096, 4096);
+            case 1 -> random.nextInt(-30_000_000, 30_000_000);
+            case 2 -> random.nextInt(-512, 512) + random.nextDouble();
+            case 3 -> random.nextInt(-64, 64) * 6;
+            case 4 -> random.nextDouble(-30_000_000D, 30_000_000D);
+            default -> random.nextInt(-16, 16) * 0.25D;
+        };
+    }
+
+    private static IrisGenerator generator(SplittableRandom random) {
+        int layers = 1 + random.nextInt(3);
+        KList<IrisNoiseGenerator> composite = new KList<>();
+        for (int layer = 0; layer < layers; layer++) {
+            composite.add(layer(random, 0));
+        }
+        double[] details = {0D, 0.25D, 0.5D, 1D};
+        IrisGenerator generator = new IrisGenerator().setComposite(composite)
+                .setSurfaceDetail(details[random.nextInt(details.length)])
+                .setMultiplicitive(random.nextInt(4) == 0)
+                .setSeed(random.nextLong(-5000L, 5000L))
+                .setZoom(0.2D + random.nextDouble() * 3D)
+                .setOffsetX(random.nextInt(-40, 40) * 0.25D)
+                .setOffsetZ(random.nextInt(-40, 40) * 0.25D)
+                .setOpacity(0.1D + random.nextDouble());
+        if (random.nextInt(3) == 0) {
+            generator.setCliffHeightMin(random.nextDouble() * 4D).setCliffHeightMax(4D + random.nextDouble() * 12D)
+                    .setCliffHeightGenerator(layer(random, 2));
+        }
+        if (random.nextInt(5) == 0) {
+            generator.setCellFractureHeight(random.nextDouble()).setCellFractureZoom(0.5D + random.nextDouble());
+        }
+        return generator;
+    }
+
+    private static IrisNoiseGenerator layer(SplittableRandom random, int depth) {
+        IrisNoiseGenerator layer = new IrisNoiseGenerator()
+                .setStyle(STYLES[random.nextInt(STYLES.length)].style())
+                .setSeed(random.nextLong(-100_000L, 100_000L))
+                .setZoom(0.3D + random.nextDouble() * 4D)
+                .setOpacity(0.05D + random.nextDouble())
+                .setOffsetX(random.nextInt(-20, 20) * 0.5D)
+                .setOffsetZ(random.nextInt(-20, 20) * 0.5D)
+                .setOffsetY(random.nextInt(4) == 0 ? random.nextDouble() * 0.1D : 0D)
+                .setNegative(random.nextInt(4) == 0)
+                .setExponent(random.nextInt(4) == 0 ? 0.5D + random.nextDouble() : 1D)
+                .setParametric(random.nextInt(6) == 0)
+                .setBezier(random.nextInt(6) == 0)
+                .setSinCentered(random.nextInt(8) == 0)
+                .setOctaves(random.nextInt(5) == 0 ? 2 : 1)
+                .setEnabled(depth == 0 || random.nextInt(8) != 0);
+        if (depth < 4 && random.nextInt(3) != 0) {
+            int children = random.nextInt(4) == 0 ? 2 + random.nextInt(2) : 1;
+            KList<IrisNoiseGenerator> fracture = new KList<>();
+            for (int child = 0; child < children; child++) {
+                fracture.add(layer(random, depth + 1));
+            }
+            layer.setFracture(fracture);
+        }
+        return layer;
+    }
+}
diff --git a/core/src/test/java/art/arcane/iris/generation/noise/IrisGeneratorBatchTest.java b/core/src/test/java/art/arcane/iris/generation/noise/IrisGeneratorBatchTest.java
index 7d984d9da..144f8da56 100644
--- a/core/src/test/java/art/arcane/iris/generation/noise/IrisGeneratorBatchTest.java
+++ b/core/src/test/java/art/arcane/iris/generation/noise/IrisGeneratorBatchTest.java
@@ -3,9 +3,6 @@ package art.arcane.iris.generation.noise;
 import art.arcane.volmlib.util.collection.KList;
 import org.junit.Test;
 
-import java.util.ArrayList;
-import java.util.List;
-
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertThrows;
@@ -34,7 +31,7 @@ public class IrisGeneratorBatchTest {
                     assertTrue(batch.supportsBatch());
                     double[] sampled = new double[XS.length];
                     for (long seed : seeds) {
-                        batch.getHeights(XS, ZS, seed, sampled, sampled.length);
+                        batch.compileProgram(seed).heights(new TerrainBatchScratch(), XS, ZS, sampled.length, sampled);
                         for (int index = 0; index < sampled.length; index++) {
                             assertEquals(style + " detail=" + detail + " seed=" + seed + " index=" + index,
                                     Double.doubleToRawLongBits(scalar.getHeight(XS[index], ZS[index], seed)),
@@ -54,7 +51,7 @@ public class IrisGeneratorBatchTest {
                 IrisGenerator batch = generator(style, detail, false).setCliffHeightMax(0D).setCellFractureHeight(0D);
                 double[] values = new double[XS.length];
                 for (long seed : new long[]{-1337L, Long.MAX_VALUE - 37L}) {
-                    batch.getHeights(XS, ZS, seed, values, XS.length);
+                    batch.compileProgram(seed).heights(new TerrainBatchScratch(), XS, ZS, XS.length, values);
                     for (int index = 0; index < XS.length; index++) {
                         assertEquals(Double.doubleToRawLongBits(scalar.getHeight(XS[index], ZS[index], seed)),
                                 Double.doubleToRawLongBits(values[index]));
@@ -65,13 +62,15 @@ public class IrisGeneratorBatchTest {
     }
 
     @Test
-    public void resolvesLayerContextOncePerBatch() {
+    public void resolvesLayerContextOncePerCompile() {
         IrisNoiseGenerator layer = spy(new IrisNoiseGenerator().setStyle(NoiseStyle.SIMPLEX.style()));
         IrisGenerator generator = new IrisGenerator().setComposite(new KList<>(layer));
         double[] sampled = new double[XS.length];
-        generator.getHeights(XS, ZS, 99L, sampled, XS.length);
+        GeneratorProgram program = generator.compileProgram(99L);
         verify(layer, times(1)).getGenerator(anyLong(), isNull(), isNull());
         clearInvocations(layer);
+        program.heights(new TerrainBatchScratch(), XS, ZS, XS.length, sampled);
+        verify(layer, times(0)).getGenerator(anyLong(), isNull(), isNull());
         for (int index = 0; index < XS.length; index++) {
             generator.getHeight(XS[index], ZS[index], 99L);
         }
@@ -79,24 +78,15 @@ public class IrisGeneratorBatchTest {
     }
 
     @Test
-    public void customGeneratorFallbackKeepsCoordinateOrder() {
-        List<Double> sampled = new ArrayList<>();
+    public void customGeneratorsCannotCompile() {
         IrisGenerator generator = new IrisGenerator() {
             @Override
             public double getHeight(double x, double z, long seed) {
-                sampled.add(x);
-                return sampled.size();
+                return x;
             }
         };
         assertFalse(generator.supportsBatch());
-        double[] values = new double[XS.length];
-        generator.getHeights(XS, ZS, 0L, values, values.length);
-        for (int index = 0; index < values.length; index++) {
-            assertEquals(Double.valueOf(XS[index]), sampled.get(index));
-            assertEquals(index + 1D, values[index], 0D);
-        }
-        assertThrows(IllegalArgumentException.class,
-                () -> generator.getHeights(new double[4097], new double[4097], 0L, new double[4097], 4097));
+        assertThrows(IllegalStateException.class, () -> generator.compileProgram(0L));
     }
 
     @Test
diff --git a/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexBakeParityTest.java b/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexBakeParityTest.java
new file mode 100644
index 000000000..ec36ad135
--- /dev/null
+++ b/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexBakeParityTest.java
@@ -0,0 +1,204 @@
+package art.arcane.iris.generation.runtime;
+
+import art.arcane.iris.configuration.IrisSettings;
+import art.arcane.iris.generation.bake.BakePlane;
+import art.arcane.iris.generation.bake.GeneratorEvaluations;
+import art.arcane.iris.generation.block.B;
+import art.arcane.iris.generation.image.IrisImageMapApplication;
+import art.arcane.iris.generation.image.IrisImageMapRuntime;
+import art.arcane.iris.generation.terrain.IrisDimension;
+import art.arcane.iris.pack.loading.IrisData;
+import art.arcane.iris.spi.IrisPlatform;
+import art.arcane.iris.spi.IrisPlatforms;
+import art.arcane.iris.spi.IrisServices;
+import art.arcane.iris.testsupport.PlatformLeakGuard;
+import art.arcane.volmlib.nativelib.terrain.NativeBlockState;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.ClassRule;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+import org.mockito.MockedStatic;
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.SplittableRandom;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Answers.CALLS_REAL_METHODS;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyDouble;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.mockStatic;
+import static org.mockito.Mockito.when;
+
+public class IrisComplexBakeParityTest {
+    @ClassRule public static final PlatformLeakGuard PLATFORM_GUARD = PlatformLeakGuard.clean();
+    @Rule public TemporaryFolder temporaryFolder = new TemporaryFolder();
+
+    private IrisSettings previousSettings;
+
+    @Before
+    public void prepareRuntime() {
+        previousSettings = IrisSettings.settings;
+        IrisSettings.settings = new IrisSettings();
+        IrisServices.register(PreservationRegistry.class, mock(PreservationRegistry.class));
+        IrisPlatform platform = mock(IrisPlatform.class);
+        when(platform.platformName()).thenReturn("bukkit");
+        IrisPlatforms.bind(platform);
+    }
+
+    @After
+    public void releaseRuntime() {
+        IrisPlatforms.unbind();
+        IrisServices.remove(PreservationRegistry.class);
+        IrisSettings.settings = previousSettings;
+    }
+
+    @Test
+    public void batchedChunkBaseHeightsEqualScalarHeightsBitForBit() throws Exception {
+        try (Statics ignored = new Statics(); Fixture batched = new Fixture(pack()); Fixture scalar = new Fixture(pack())) {
+            SplittableRandom random = new SplittableRandom(0xBA5EL);
+            for (int chunk = 0; chunk < 48; chunk++) {
+                int chunkX = random.nextInt(-400, 400);
+                int chunkZ = random.nextInt(-400, 400);
+                double[] baked = (double[]) batched.complex.bakePlane(BakePlane.BASE_HEIGHT, chunkX, chunkZ);
+                for (int index = 0; index < 256; index++) {
+                    int x = (chunkX << 4) + (index & 15);
+                    int z = (chunkZ << 4) + (index >> 4);
+                    assertEquals("chunk " + chunkX + "," + chunkZ + " column " + index,
+                            Double.doubleToRawLongBits(scalar.complex.getBaseTerrainHeightStream().getDouble(x, z)),
+                            Double.doubleToRawLongBits(baked[index]));
+                }
+            }
+        }
+    }
+
+    @Test
+    public void batchedChunksEvaluateExactlyTheScalarGeneratorSet() throws Exception {
+        try (Statics ignored = new Statics(); Fixture batched = new Fixture(pack()); Fixture scalar = new Fixture(pack())) {
+            SplittableRandom random = new SplittableRandom(0xC0DEL);
+            long totalBatched = 0L;
+            for (int chunk = 0; chunk < 32; chunk++) {
+                int chunkX = random.nextInt(-400, 400);
+                int chunkZ = random.nextInt(-400, 400);
+                GeneratorEvaluations.Snapshot before = GeneratorEvaluations.snapshot();
+                batched.complex.bakePlane(BakePlane.BASE_HEIGHT, chunkX, chunkZ);
+                GeneratorEvaluations.Snapshot afterBatch = GeneratorEvaluations.snapshot();
+                for (int index = 0; index < 256; index++) {
+                    scalar.complex.getBaseTerrainHeightStream().getDouble((chunkX << 4) + (index & 15), (chunkZ << 4) + (index >> 4));
+                }
+                GeneratorEvaluations.Snapshot afterScalar = GeneratorEvaluations.snapshot();
+                long batchedEvaluations = afterBatch.minus(before).bakedEvaluations();
+                assertEquals(0L, afterBatch.minus(before).scalarEvaluations());
+                assertEquals("chunk " + chunkX + "," + chunkZ, batchedEvaluations,
+                        afterScalar.minus(afterBatch).scalarEvaluations());
+                totalBatched += batchedEvaluations;
+            }
+            assertTrue(totalBatched > 0L);
+        }
+    }
+
+    private Path pack() throws Exception {
+        Path pack = temporaryFolder.newFolder().toPath();
+        Files.createDirectories(pack.resolve("dimensions"));
+        Files.createDirectories(pack.resolve("regions"));
+        Files.createDirectories(pack.resolve("biomes"));
+        Files.createDirectories(pack.resolve("generators"));
+        Files.writeString(pack.resolve("dimensions/main.json"), """
+                {"regions":["alpha","beta"],"landChance":0.55,"regionZoom":0.2,"biomeZoom":0.15,
+                 "carvingEnabled":false,"hydrology":{"rivers":{"enabled":false}}}
+                """);
+        Files.writeString(pack.resolve("regions/alpha.json"),
+                "{\"landBiomes\":[\"peaks\",\"meadow\",\"dunes\"],\"seaBiomes\":[\"sea\"],\"rarity\":1}");
+        Files.writeString(pack.resolve("regions/beta.json"),
+                "{\"landBiomes\":[\"meadow\",\"spires\"],\"seaBiomes\":[\"sea\"],\"rarity\":2}");
+        generator(pack, "mountain", "BILINEAR_STARCAST_9", 52, 0.5D, """
+                [{"style":{"style":"FRACTAL_SMOKE","zoom":1},"seed":3356}]""", "");
+        generator(pack, "magnet", "BILINEAR_STARCAST_9", 52, 0.5D, """
+                [{"style":{"style":"FRACTAL_SMOKE","zoom":0.6},"seed":911}]""", "");
+        generator(pack, "plain", "BILINEAR_STARCAST_9", 12, 0.5D, """
+                [{"style":{"style":"IRIS_DOUBLE","zoom":0.87,"fracture":{"style":"NOWHERE","zoom":0.195,"multiplier":18}},"seed":10056,"bezier":true}]""", "");
+        generator(pack, "cliffs", "BILINEAR_STARCAST_9", 12, 0.5D, """
+                [{"style":{"style":"GLOB","zoom":0.4,"exponent":0.7,"fracture":{"style":"NOWHERE","zoom":0.1,"multiplier":5}},"negative":true,"seed":10056}]""",
+                ",\"cliffHeightMax\":80,\"cliffHeightMin\":35,\"cliffHeightGenerator\":{\"seed\":2348,\"style\":{\"style\":\"CELLULAR_HEIGHT\"},\"zoom\":0.4}");
+        generator(pack, "dunes", "BILINEAR_STARCAST_9", 23, 1D, """
+                [{"style":{"style":"SIMPLEX","zoom":2},"seed":77,"fracture":[{"style":{"style":"PERLIN"},"seed":5,"opacity":2.5}]}]""", "");
+        generator(pack, "spikes", "STARCAST_12", 42, 0D, """
+                [{"style":{"style":"CELLULAR","zoom":0.5},"seed":4}]""", "");
+        biome(pack, "peaks", "[{\"generator\":\"mountain\",\"min\":40,\"max\":120},{\"generator\":\"spikes\",\"min\":0,\"max\":20}]",
+                ",\"children\":[\"meadow\"],\"childShrinkFactor\":1.5");
+        biome(pack, "meadow", "[{\"generator\":\"plain\",\"min\":2,\"max\":14},{\"generator\":\"cliffs\",\"min\":0,\"max\":9}]", "");
+        biome(pack, "dunes", "[{\"generator\":\"dunes\",\"min\":3,\"max\":30},{\"generator\":\"magnet\",\"min\":-4,\"max\":6}]", "");
+        biome(pack, "spires", "[{\"generator\":\"spikes\",\"min\":10,\"max\":60},{\"generator\":\"plain\",\"min\":1,\"max\":4}]", "");
+        biome(pack, "sea", "[{\"generator\":\"mountain\",\"min\":-32,\"max\":-10}]", "");
+        return pack;
+    }
+
+    private static void generator(Path pack, String key, String function, double scale, double detail,
+                                  String composite, String extra) throws Exception {
+        Files.writeString(pack.resolve("generators/" + key + ".json"), "{\"surfaceDetail\":" + detail
+                + ",\"interpolator\":{\"function\":\"" + function + "\",\"horizontalScale\":" + scale + "}"
+                + ",\"seed\":" + Math.abs(key.hashCode()) + ",\"composite\":" + composite.strip() + extra + "}");
+    }
+
+    private static void biome(Path pack, String key, String generators, String extra) throws Exception {
+        Files.writeString(pack.resolve("biomes/" + key + ".json"), "{\"generators\":" + generators + extra + "}");
+    }
+
+    private static final class Statics implements AutoCloseable {
+        private final MockedStatic<B> blocks = mockStatic(B.class);
+        private final MockedStatic<IrisImageMapRuntime> imageRuntimes = mockStatic(IrisImageMapRuntime.class);
+
+        private Statics() {
+            NativeBlockState block = mock(NativeBlockState.class);
+            when(block.isFluid()).thenReturn(true);
+            blocks.when(() -> B.getState(anyString())).thenReturn(block);
+            blocks.when(() -> B.getStateOrNull(anyString(), eq(false))).thenReturn(block);
+            IrisImageMapRuntime images = mock(IrisImageMapRuntime.class);
+            when(images.has(IrisImageMapApplication.BIOME)).thenReturn(false);
+            when(images.sampleTerrainHeight(anyDouble(), anyDouble(), anyDouble()))
+                    .thenAnswer(invocation -> invocation.<Double>getArgument(2));
+            imageRuntimes.when(() -> IrisImageMapRuntime.compile(any(Engine.class))).thenReturn(images);
+        }
+
+        @Override
+        public void close() {
+            imageRuntimes.close();
+            blocks.close();
+        }
+    }
+
+    private static final class Fixture implements AutoCloseable {
+        private final Engine engine = mock(Engine.class, CALLS_REAL_METHODS);
+        private final EnginePlatformHooks hooks = mock(EnginePlatformHooks.class);
+        private final IrisData data;
+        private final IrisComplex complex;
+
+        private Fixture(Path pack) {
+            data = IrisData.openRuntime(pack.toFile());
+            IrisDimension dimension = data.getDimensionLoader().load("main");
+            doReturn(data).when(engine).getData();
+            doReturn(dimension).when(engine).getDimension();
+            doReturn(384).when(engine).getHeight();
+            doReturn(-64).when(engine).getMinHeight();
+            doReturn(320).when(engine).getMaxHeight();
+            when(hooks.isMainThread()).thenReturn(false);
+            doReturn(hooks).when(engine).getPlatformHooks();
+            doReturn(new SeedManager(1337L)).when(engine).getSeedManager();
+            complex = new IrisComplex(engine);
+            doReturn(complex).when(engine).getComplex();
+        }
+
+        @Override
+        public void close() {
+            complex.close();
+            data.close();
+        }
+    }
+}
diff --git a/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexHeightStreamTest.java b/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexHeightStreamTest.java
index 1e0dbbac0..8f0829a1c 100644
--- a/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexHeightStreamTest.java
+++ b/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexHeightStreamTest.java
@@ -44,6 +44,7 @@ import static org.mockito.ArgumentMatchers.anyDouble;
 import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.atMost;
 import static org.mockito.Mockito.clearInvocations;
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.mock;
@@ -89,16 +90,10 @@ public class IrisComplexHeightStreamTest {
         try (Fixture fixture = new Fixture(pack())) {
             IrisBiome mapped = new IrisBiome();
             when(fixture.images.sampleBiome(anyDouble(), anyDouble())).thenReturn(mapped);
-            MeteredCache bridge = (MeteredCache) fixture.complex.getBridgeStream();
-            MeteredCache regions = (MeteredCache) fixture.complex.getRegionStream();
-            MeteredCache heights = (MeteredCache) fixture.complex.getNaturalHeightStream();
             assertSame(mapped, fixture.complex.getBaseBiomeStream().get(-16, 32));
             assertSame(mapped, fixture.complex.getBaseBiomeStream().get(-16.75, 10, 32.5));
             assertSame(mapped, fixture.complex.getNaturalTrueBiomeStream().get(-16, 32));
             assertSame(mapped, fixture.complex.getNaturalTrueBiomeStream().get(-16.75, 10, 32.5));
-            assertEquals(0L, bridge.getSize());
-            assertEquals(0L, regions.getSize());
-            assertEquals(0L, heights.getSize());
             assertNull(fixture.complex.getSharedCornerBounds());
 
             when(fixture.images.sampleBiome(anyDouble(), anyDouble())).thenReturn(null);
@@ -116,7 +111,7 @@ public class IrisComplexHeightStreamTest {
             int[] rounded = new int[256];
             clearInvocations(fixture.hooks);
             cache.fillRounded(rounded);
-            verify(fixture.hooks, times(1)).isMainThread();
+            verify(fixture.hooks, atMost(2)).isMainThread();
             assertEquals(256, samples.get());
             for (int index = 0; index < 256; index++) {
                 int x = index & 15;
@@ -127,7 +122,7 @@ public class IrisComplexHeightStreamTest {
             }
             clearInvocations(fixture.hooks);
             cache.fill();
-            verify(fixture.hooks, times(1)).isMainThread();
+            verify(fixture.hooks, atMost(2)).isMainThread();
             assertEquals(256, samples.get());
         }
     }
diff --git a/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexHydrologyNoiseCacheTest.java b/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexHydrologyNoiseCacheTest.java
index be0ae4f35..e18d0bc1e 100644
--- a/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexHydrologyNoiseCacheTest.java
+++ b/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexHydrologyNoiseCacheTest.java
@@ -2,6 +2,8 @@ package art.arcane.iris.generation.runtime;
 
 import art.arcane.iris.configuration.IrisSettings;
 import art.arcane.iris.world.pregen.PregenPerformanceProfile;
+import art.arcane.iris.generation.bake.ChunkBakeCache;
+import art.arcane.iris.generation.bake.PlaneSource;
 import art.arcane.iris.generation.biome.IrisBiome;
 import art.arcane.iris.generation.hydrology.HydrologyPlanner;
 import art.arcane.iris.generation.hydrology.HydrologyPlannerSettings;
@@ -48,17 +50,14 @@ public class IrisComplexHydrologyNoiseCacheTest {
         try (Fixture fixture = new Fixture(1_024)) {
             ProceduralStream<Double> wrapper = fixture.complex.getRawHeightStream();
             assertEquals(13D, fixture.height.getDouble(18, 5), 0D);
-            assertEquals(13D, fixture.rawHeight.getDouble(18, 5), 0D);
 
             PregenPerformanceProfile.apply(fixture.engine);
 
-            assertEquals(4_096L * 256L, fixture.height.getMaxSize());
-            assertEquals(4_096L * 256L, fixture.rawHeight.getMaxSize());
+            assertTrue(fixture.bakes.capacity() >= 4_096);
             assertEquals(1_024L * 256L, fixture.biomes.getMaxSize());
             assertSame(wrapper, fixture.complex.getRawHeightStream());
             assertEquals(47D, wrapper.getDouble(18, 5), 0D);
             assertEquals(13D, fixture.height.getDouble(18, 5), 0D);
-            assertEquals(13D, fixture.rawHeight.getDouble(18, 5), 0D);
         } finally {
             PregenPerformanceProfile.restore();
             IrisSettings.settings = previousSettings;
@@ -75,7 +74,7 @@ public class IrisComplexHydrologyNoiseCacheTest {
             fixture.complex.ensureTerrainNoiseCacheSize(4_096);
 
             fixture.assertCapacities(32_768);
-            assertEquals(4_096L * 256L, fixture.rawHeight.getMaxSize());
+            assertTrue(fixture.bakes.capacity() >= 4_096);
             assertEquals(reservedBytes, budget.reservedBytes());
             fixture.complex.close();
             assertEquals(0L, budget.reservedBytes());
@@ -88,7 +87,7 @@ public class IrisComplexHydrologyNoiseCacheTest {
             fixture.complex.ensureTerrainNoiseCacheSize(4_096);
 
             fixture.assertCapacities(65_536);
-            assertEquals(65_536L * 256L, fixture.rawHeight.getMaxSize());
+            assertTrue(fixture.bakes.capacity() >= 65_536);
         }
     }
 
@@ -229,11 +228,54 @@ public class IrisComplexHydrologyNoiseCacheTest {
             HydrologyNoiseCacheBudget budget = new HydrologyNoiseCacheBudget(Long.MAX_VALUE);
             setField(fixture.complex, "detached", true);
             fixture.complex.expandHydrologyNoiseCaches(budget);
+            fixture.complex.reserveHydrologyBake(budget);
             fixture.assertCapacities(1_024);
+            assertEquals(1_024, fixture.bakes.capacity());
             setField(fixture.complex, "detached", false);
             fixture.complex.setHydrologyRuntime(null);
             fixture.complex.expandHydrologyNoiseCaches(budget);
+            fixture.complex.reserveHydrologyBake(budget);
             fixture.assertCapacities(1_024);
+            assertEquals(1_024, fixture.bakes.capacity());
+            assertEquals(0L, budget.reservedBytes());
+        }
+    }
+
+    @Test
+    public void plannerReservationGrowsTheBakeToTheHydrologyTarget() throws Exception {
+        try (Fixture fixture = new Fixture(1_024)) {
+            HydrologyNoiseCacheBudget budget = new HydrologyNoiseCacheBudget(Long.MAX_VALUE);
+            fixture.complex.reserveHydrologyBake(budget);
+            fixture.complex.reserveHydrologyBake(budget);
+            assertEquals(32_768, fixture.bakes.capacity());
+            assertEquals(2L * (32_768L - 1_024L) * 4_096L, budget.reservedBytes());
+            fixture.complex.ensureTerrainNoiseCacheSize(4_096);
+            assertEquals(32_768, fixture.bakes.capacity());
+            fixture.complex.close();
+            assertEquals(0L, budget.reservedBytes());
+            fixture.complex.reserveHydrologyBake(budget);
+            assertEquals(0L, budget.reservedBytes());
+        }
+    }
+
+    @Test
+    public void plannerReservationTakesOnlyTheGrantedShareOfTheBudget() throws Exception {
+        try (Fixture fixture = new Fixture(1_024)) {
+            HydrologyNoiseCacheBudget budget = new HydrologyNoiseCacheBudget(2L * 80L * 4_096L + 4_095L);
+            fixture.complex.reserveHydrologyBake(budget);
+            assertEquals(1_104, fixture.bakes.capacity());
+            assertEquals(2L * 80L * 4_096L, budget.reservedBytes());
+            fixture.complex.close();
+            assertEquals(0L, budget.reservedBytes());
+        }
+    }
+
+    @Test
+    public void plannerReservationLeavesLargerBakesUnchanged() throws Exception {
+        try (Fixture fixture = new Fixture(65_536)) {
+            HydrologyNoiseCacheBudget budget = new HydrologyNoiseCacheBudget(Long.MAX_VALUE);
+            fixture.complex.reserveHydrologyBake(budget);
+            assertEquals(65_536, fixture.bakes.capacity());
             assertEquals(0L, budget.reservedBytes());
         }
     }
@@ -297,7 +339,7 @@ public class IrisComplexHydrologyNoiseCacheTest {
         private final CachedStream2D<IrisRegion> regions;
         private final CachedStream2D<InferredType> bridge;
         private final CachedDoubleStream2D height;
-        private final CachedDoubleStream2D rawHeight;
+        private final ChunkBakeCache bakes;
 
         private Fixture(int capacity) throws Exception {
             services.when(() -> IrisServices.get(PreservationRegistry.class)).thenReturn(mock(PreservationRegistry.class));
@@ -305,10 +347,10 @@ public class IrisComplexHydrologyNoiseCacheTest {
             regions = objectCache(capacity);
             bridge = objectCache(capacity);
             height = heightCache(capacity);
-            rawHeight = heightCache(capacity);
+            bakes = new ChunkBakeCache(mock(PlaneSource.class), capacity);
             complex.setNaturalHeightStream(height);
             complex.setHeightStream(ProceduralStream.ofDouble((x, z) -> 47D));
-            setField(complex, "cachedHeightStream", rawHeight);
+            setField(complex, "bakeCache", bakes);
             when(engine.getComplex()).thenReturn(complex);
             complex.setBaseBiomeStream(biomes);
             complex.setRegionStream(regions);
diff --git a/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexSelfSelectionTest.java b/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexSelfSelectionTest.java
index 4d68fd070..b0e7aedd6 100644
--- a/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexSelfSelectionTest.java
+++ b/core/src/test/java/art/arcane/iris/generation/runtime/IrisComplexSelfSelectionTest.java
@@ -83,7 +83,7 @@ public class IrisComplexSelfSelectionTest {
             Field field = IrisComplex.class.getDeclaredField("childSelectionPlans");
             field.setAccessible(true);
             field.set(complex, plans);
-            implode = IrisComplex.class.getDeclaredMethod("implode", IrisBiome.class, Double.class, Double.class, int.class);
+            implode = IrisComplex.class.getDeclaredMethod("implode", IrisBiome.class, double.class, double.class, int.class);
             implode.setAccessible(true);
         }
 
@@ -106,7 +106,7 @@ public class IrisComplexSelfSelectionTest {
         }
 
         @Override
-        public CNG getChildrenGenerator(RNG rng, int signature, double scale) {
+        public CNG getChildrenGenerator(long seed, double scale) {
             return noise;
         }
     }
diff --git a/core/src/test/java/art/arcane/iris/generation/stage/IrisCarveModifierInferenceIsolationTest.java b/core/src/test/java/art/arcane/iris/generation/stage/IrisCarveModifierInferenceIsolationTest.java
index ca9f39398..d0eb081fb 100644
--- a/core/src/test/java/art/arcane/iris/generation/stage/IrisCarveModifierInferenceIsolationTest.java
+++ b/core/src/test/java/art/arcane/iris/generation/stage/IrisCarveModifierInferenceIsolationTest.java
@@ -97,11 +97,11 @@ public class IrisCarveModifierInferenceIsolationTest {
         doReturn(0D).when(region).getShoreHeight(anyDouble(), anyDouble());
         Method fixBiomeType = IrisComplex.class.getDeclaredMethod(
                 "fixBiomeType",
-                Double.class,
+                double.class,
                 IrisBiome.class,
                 IrisRegion.class,
-                Double.class,
-                Double.class,
+                double.class,
+                double.class,
                 double.class
         );
         fixBiomeType.setAccessible(true);
diff --git a/core/src/test/java/art/arcane/iris/generation/stream/RarityStreamTest.java b/core/src/test/java/art/arcane/iris/generation/stream/RarityStreamTest.java
new file mode 100644
index 000000000..c3dee77dd
--- /dev/null
+++ b/core/src/test/java/art/arcane/iris/generation/stream/RarityStreamTest.java
@@ -0,0 +1,52 @@
+package art.arcane.iris.generation.stream;
+
+import art.arcane.volmlib.util.math.Rarity;
+import art.arcane.volmlib.util.stream.ProceduralStream;
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.SplittableRandom;
+
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertSame;
+
+public class RarityStreamTest {
+    @Test
+    public void picksMatchRarityStreamSelectionForEveryNoiseValue() {
+        SplittableRandom random = new SplittableRandom(4242L);
+        for (int trial = 0; trial < 200; trial++) {
+            List<Option> options = new ArrayList<>();
+            int count = 1 + random.nextInt(12);
+            for (int index = 0; index < count; index++) {
+                options.add(new Option(random.nextInt(-2, 40)));
+            }
+            double[] value = new double[1];
+            ProceduralStream<Double> noise = ProceduralStream.ofDouble((x, z) -> value[0]);
+            ProceduralStream<Option> expected = noise.selectRarity(options);
+            RarityStream<Option> candidate = new RarityStream<>(noise, options);
+            for (int sample = 0; sample < 2_000; sample++) {
+                value[0] = switch (random.nextInt(5)) {
+                    case 0 -> random.nextDouble();
+                    case 1 -> random.nextDouble(-0.5D, 1.5D);
+                    case 2 -> random.nextInt(0, 64) / 63D;
+                    case 3 -> sample % 2 == 0 ? Double.NaN : -0D;
+                    default -> Math.nextUp(random.nextInt(0, 16) / 15D);
+                };
+                assertSame(expected.get(sample, -sample), candidate.get(sample, -sample));
+            }
+        }
+    }
+
+    @Test
+    public void emptyOptionsSelectNothing() {
+        assertNull(new RarityStream<Option>(ProceduralStream.ofDouble((x, z) -> 0.5D), List.of()).get(0D, 0D));
+    }
+
+    private record Option(int rarity) implements Rarity {
+        @Override
+        public int getRarity() {
+            return rarity;
+        }
+    }
+}
diff --git a/core/src/test/java/art/arcane/iris/structure/object/IrisObjectPlacementRunnerRegressionTest.java b/core/src/test/java/art/arcane/iris/structure/object/IrisObjectPlacementRunnerRegressionTest.java
index 4aed16c6f..f867da5af 100644
--- a/core/src/test/java/art/arcane/iris/structure/object/IrisObjectPlacementRunnerRegressionTest.java
+++ b/core/src/test/java/art/arcane/iris/structure/object/IrisObjectPlacementRunnerRegressionTest.java
@@ -791,7 +791,7 @@ public class IrisObjectPlacementRunnerRegressionTest {
 
                     object.place(0, ANCHOR_Y, 0, placer, placement, new RNG(2L), data);
 
-                    assertEquals(1, placer.blockReads);
+                    assertEquals(enabled || authored ? 1 : 0, placer.blockReads);
                     assertEquals(1, placer.writes().size());
                     assertSame(submerged && (enabled || authored) ? wet : dry,
                             placer.writes().get(0).state());
diff --git a/core/src/test/java/art/arcane/iris/structure/object/ObjectPlacementBakeTest.java b/core/src/test/java/art/arcane/iris/structure/object/ObjectPlacementBakeTest.java
new file mode 100644
index 000000000..1a51d26be
--- /dev/null
+++ b/core/src/test/java/art/arcane/iris/structure/object/ObjectPlacementBakeTest.java
@@ -0,0 +1,76 @@
+package art.arcane.iris.structure.object;
+
+import art.arcane.iris.generation.geometry.IrisBlockVector;
+import art.arcane.iris.testsupport.KeyedBlockState;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotSame;
+import static org.junit.Assert.assertSame;
+
+public class ObjectPlacementBakeTest {
+    @Test
+    public void spinsResolvingToTheSameKernelShareOneBake() {
+        IrisObject object = object();
+        IrisObjectRotation rotation = new IrisObjectRotation();
+
+        ObjectPlacementBake first = ObjectPlacementBake.of(object, new SpinKernel(rotation, 0, 10, 0), false, null);
+        ObjectPlacementBake second = ObjectPlacementBake.of(object, new SpinKernel(rotation, 3, 80, 9), false, null);
+        ObjectPlacementBake turned = ObjectPlacementBake.of(object, new SpinKernel(rotation, 0, 100, 0), false, null);
+
+        assertSame(first, second);
+        assertNotSame(first, turned);
+        assertEquals(3, first.count());
+    }
+
+    @Test
+    public void bakedOffsetsMatchTheKernelTransformInCursorOrder() {
+        IrisObject object = object();
+        IrisObjectRotation rotation = IrisObjectRotation.of(0D, 90D, 0D);
+        SpinKernel spin = new SpinKernel(rotation, 0, 0, 0);
+        IrisBlockVector translate = new IrisBlockVector(1.5D, -2D, 0.25D);
+
+        ObjectPlacementBake bake = ObjectPlacementBake.of(object, spin, true, translate);
+        double[] exact = bake.exact(object, spin);
+
+        int index = 0;
+        for (IrisBlockVector source : object.getBlocks().keys()) {
+            IrisBlockVector expected = source.clone();
+            spin.rotate(expected);
+            expected.setY(-expected.getBlockY());
+            expected.add(translate);
+            assertEquals((int) Math.round(expected.getX()), bake.offsetX(index));
+            assertEquals((int) Math.round(expected.getY()), bake.offsetY(index));
+            assertEquals((int) Math.round(expected.getZ()), bake.offsetZ(index));
+            assertEquals(expected.getBlockY(), bake.layerY(index));
+            assertEquals(expected.getX(), exact[index * 3], 0D);
+            assertEquals(expected.getY(), exact[index * 3 + 1], 0D);
+            assertEquals(expected.getZ(), exact[index * 3 + 2], 0D);
+            index++;
+        }
+        assertEquals(bake.count(), index);
+    }
+
+    @Test
+    public void editedObjectsRebake() {
+        IrisObject object = object();
+        SpinKernel spin = new SpinKernel(new IrisObjectRotation(), 0, 0, 0);
+        ObjectPlacementBake before = ObjectPlacementBake.of(object, spin, false, null);
+
+        object.getBlocks().put(new IrisBlockVector(1, 1, 1), new KeyedBlockState("minecraft:dirt"));
+        ObjectPlacementBake after = ObjectPlacementBake.of(object, spin, false, null);
+
+        assertNotSame(before, after);
+        assertEquals(4, after.count());
+        assertSame(after, ObjectPlacementBake.of(object, spin, false, null));
+    }
+
+    private static IrisObject object() {
+        IrisObject object = new IrisObject(5, 5, 5);
+        KeyedBlockState stone = new KeyedBlockState("minecraft:stone");
+        object.getBlocks().put(new IrisBlockVector(-2, 0, 1), stone);
+        object.getBlocks().put(new IrisBlockVector(0, -1, 2), stone);
+        object.getBlocks().put(new IrisBlockVector(2, 2, -2), new KeyedBlockState("minecraft:oak_log[axis=y]"));
+        return object;
+    }
+}
diff --git a/core/src/test/java/art/arcane/iris/structure/object/ObjectPlacementGoldenTest.java b/core/src/test/java/art/arcane/iris/structure/object/ObjectPlacementGoldenTest.java
new file mode 100644
index 000000000..60b4ad93c
--- /dev/null
+++ b/core/src/test/java/art/arcane/iris/structure/object/ObjectPlacementGoldenTest.java
@@ -0,0 +1,761 @@
+package art.arcane.iris.structure.object;
+
+import art.arcane.iris.generation.block.BlockDataMergeSupport;
+import art.arcane.iris.generation.block.IrisBlockData;
+import art.arcane.iris.generation.block.TileData;
+import art.arcane.iris.generation.cave.CarvingMode;
+import art.arcane.iris.generation.decoration.IrisStiltSettings;
+import art.arcane.iris.generation.decoration.IrisVacuumSettings;
+import art.arcane.iris.generation.decoration.tree.TreeBlockCanvas;
+import art.arcane.iris.generation.decoration.tree.TreeGrounding;
+import art.arcane.iris.generation.geometry.IrisBlockVector;
+import art.arcane.iris.generation.noise.IrisGeneratorStyle;
+import art.arcane.iris.generation.noise.NoiseStyle;
+import art.arcane.iris.generation.runtime.Engine;
+import art.arcane.iris.generation.runtime.IrisComplex;
+import art.arcane.iris.generation.terrain.IrisDimension;
+import art.arcane.iris.generation.terrain.IrisMaterialPalette;
+import art.arcane.iris.pack.loading.IrisData;
+import art.arcane.iris.pack.loading.ResourceLoader;
+import art.arcane.iris.pack.validation.ContentGate;
+import art.arcane.iris.spi.IrisPlatform;
+import art.arcane.iris.spi.IrisPlatforms;
+import art.arcane.iris.spi.PlatformRegistries;
+import art.arcane.iris.testsupport.PlatformLeakGuard;
+import art.arcane.iris.world.entity.IrisMarker;
+import art.arcane.volmlib.nativelib.terrain.NativeBlockState;
+import art.arcane.volmlib.util.collection.KList;
+import art.arcane.volmlib.util.collection.KMap;
+import art.arcane.volmlib.util.math.BlockPosition;
+import art.arcane.volmlib.util.math.RNG;
+import art.arcane.volmlib.util.matter.MatterMarker;
+import art.arcane.volmlib.util.stream.ProceduralStream;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.ClassRule;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Random;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.ArgumentMatchers.anyBoolean;
+import static org.mockito.ArgumentMatchers.anyDouble;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+import static org.mockito.Mockito.withSettings;
+
+public class ObjectPlacementGoldenTest {
+    @ClassRule
+    public static final PlatformLeakGuard PLATFORM_GUARD = PlatformLeakGuard.clean();
+
+    private static final int OBJECTS = 200;
+    private static final int SEEDS = 5;
+    private static final long GOLDEN = 0x408f9d4113015897L;
+    private static final long MARKER_GOLDEN = 0x60b4bbf1144b239cL;
+
+    private static final List<String> PALETTE = List.of(
+            "minecraft:stone",
+            "minecraft:dirt",
+            "minecraft:grass_block[snowy=false]",
+            "minecraft:oak_log[axis=y]",
+            "minecraft:oak_log[axis=x]",
+            "minecraft:oak_leaves[distance=3,persistent=false,waterlogged=false]",
+            "minecraft:oak_leaves[distance=1,persistent=true,waterlogged=false]",
+            "minecraft:oak_leaves[distance=7,persistent=false,waterlogged=true]",
+            "minecraft:oak_stairs[facing=north,half=bottom,waterlogged=false]",
+            "minecraft:oak_stairs[facing=east,half=top,waterlogged=true]",
+            "minecraft:vine[east=false,north=true,south=false,up=false,west=false]",
+            "minecraft:air",
+            "minecraft:cave_air",
+            "minecraft:chest[facing=south,waterlogged=false]",
+            "minecraft:lantern[hanging=false,waterlogged=false]",
+            "minecraft:cobblestone",
+            "minecraft:glass",
+            "minecraft:oak_slab[type=bottom,waterlogged=false]");
+
+    private final Map<String, GoldenState> states = new ConcurrentHashMap<>();
+    private IrisData data;
+    private IrisData objectData;
+    private Engine engine;
+    private IrisObjectRotation.StateRotator previousRotator;
+    private BlockDataMergeSupport.StateMerger previousMerger;
+
+    @Before
+    public void bindPlatform() {
+        IrisPlatforms.unbind();
+        PlatformRegistries registries = mock(PlatformRegistries.class, withSettings().stubOnly());
+        when(registries.block(anyString())).thenAnswer(invocation -> state(invocation.getArgument(0)));
+        when(registries.blockOrNull(anyString())).thenAnswer(invocation -> state(invocation.getArgument(0)));
+        when(registries.blockOrNull(anyString(), anyBoolean())).thenAnswer(invocation -> state(invocation.getArgument(0)));
+        when(registries.air()).thenAnswer(invocation -> state("minecraft:air"));
+        IrisPlatform platform = mock(IrisPlatform.class, withSettings().stubOnly());
+        when(platform.registries()).thenReturn(registries);
+        IrisPlatforms.bind(platform);
+        previousRotator = IrisObjectRotation.bindPlatformRotator(ObjectPlacementGoldenTest::rotateState);
+        previousMerger = BlockDataMergeSupport.bindPlatformMerger(this::mergeStates);
+
+        ProceduralStream<NativeBlockState> rock = mock(ProceduralStream.class, withSettings().stubOnly());
+        when(rock.get(anyDouble(), anyDouble())).thenAnswer(invocation -> state("minecraft:stone"));
+        IrisComplex complex = mock(IrisComplex.class, withSettings().stubOnly());
+        when(complex.getRockStream()).thenReturn(rock);
+        IrisDimension dimension = mock(IrisDimension.class, withSettings().stubOnly());
+        engine = mock(Engine.class, withSettings().stubOnly());
+        when(engine.getHeight()).thenReturn(256);
+        when(engine.getMinHeight()).thenReturn(0);
+        when(engine.getComplex()).thenReturn(complex);
+        when(engine.getDimension()).thenReturn(dimension);
+        ContentGate gate = mock(ContentGate.class, withSettings().stubOnly());
+        when(gate.ready()).thenReturn(false);
+        data = mock(IrisData.class, withSettings().stubOnly());
+        when(data.getEngine()).thenReturn(engine);
+        when(data.getContentGate()).thenReturn(gate);
+        objectData = mock(IrisData.class, withSettings().stubOnly());
+        when(objectData.getContentGate()).thenReturn(gate);
+    }
+
+    @After
+    public void unbindPlatform() {
+        IrisObjectRotation.restorePlatformRotator(previousRotator);
+        BlockDataMergeSupport.restorePlatformMerger(previousMerger);
+        IrisPlatforms.unbind();
+    }
+
+    @Test
+    public void placementsMatchTheRecordedBlockStream() throws IOException {
+        Random random = new Random(20261021L);
+        List<IrisObjectRotation> rotations = rotations();
+        long combined = 17L;
+        StringBuilder dump = new StringBuilder();
+        for (int index = 0; index < OBJECTS; index++) {
+            IrisObject object = randomObject(random, index);
+            object.setLoader(objectData);
+            IrisObjectPlacement base = randomPlacement(random);
+            for (int rotationIndex = 0; rotationIndex < rotations.size(); rotationIndex++) {
+                IrisObjectPlacement placement = base.toPlacement("golden");
+                placement.setRotation(rotations.get(rotationIndex));
+                boolean explicitY = (index + rotationIndex) % 3 == 0;
+                for (int seed = 0; seed < SEEDS; seed++) {
+                    RNG rng = new RNG(index * 1_000_003L + rotationIndex * 7919L + seed);
+                    GoldenPlacer placer = new GoldenPlacer(engine, (index & 1) == 0);
+                    List<String> listened = new ArrayList<>();
+                    int x = 400 + index * 3 + seed;
+                    int z = -900 + rotationIndex * 5 - seed;
+                    int y = explicitY ? 90 + seed : -1;
+                    int result;
+                    if (placement.getMode() == ObjectPlaceMode.ORGANIC_STILT && explicitY && seed % 2 == 0) {
+                        result = object.placeOnFloor(x, 70, z, placer, placement, rng,
+                                (position, state) -> listened.add(position.getX() + "," + position.getY() + "," + position.getZ() + "=" + state.key()),
+                                data);
+                    } else {
+                        result = object.place(x, y, z, placer, placement, rng,
+                                (position, state) -> listened.add(position.getX() + "," + position.getY() + "," + position.getZ() + "=" + state.key()),
+                                null, data);
+                    }
+                    long hash = placer.hash;
+                    hash = mix(hash, result);
+                    hash = mix(hash, rng.nextLong());
+                    for (String entry : listened) {
+                        hash = mix(hash, entry.hashCode());
+                    }
+                    hash = mix(hash, listened.size());
+                    combined = mix(combined, hash);
+                    dump.append(index).append(' ').append(rotationIndex).append(' ').append(seed).append(' ')
+                            .append(Long.toHexString(hash)).append(' ').append(placer.writes).append('\n');
+                }
+            }
+        }
+        String dumpPath = System.getenv("IRIS_OBJECT_GOLDEN_DUMP");
+        if (dumpPath != null && !dumpPath.isBlank()) {
+            Files.writeString(Path.of(dumpPath), dump.toString());
+        }
+        assertEquals(Long.toHexString(GOLDEN), Long.toHexString(combined));
+    }
+
+    @Test
+    public void markedPlacementsMatchTheRecordedBlockStream() {
+        ResourceLoader<IrisMarker> markers = mock(ResourceLoader.class, withSettings().stubOnly());
+        IrisMarker anywhere = new IrisMarker();
+        anywhere.setEmptyAbove(false);
+        when(markers.load("anywhere")).thenReturn(anywhere);
+        when(markers.load("open")).thenReturn(new IrisMarker());
+        when(objectData.getMarkerLoader()).thenReturn(markers);
+        Random random = new Random(77L);
+        List<IrisObjectRotation> rotations = rotations();
+        long combined = 23L;
+        int markerWrites = 0;
+        for (int index = 0; index < 40; index++) {
+            IrisObject object = randomObject(random, index);
+            object.setLoader(objectData);
+            IrisObjectPlacement base = new IrisObjectPlacement();
+            base.setMode(ObjectPlaceMode.STRUCTURE_PIECE);
+            base.setRequireSurfaceSupport(false);
+            IrisObjectMarker loose = new IrisObjectMarker();
+            loose.setMarker("anywhere");
+            loose.setMaximumMarkers(1 + random.nextInt(6));
+            loose.setMark(new KList<>(new IrisBlockData("minecraft:stone"), new IrisBlockData("minecraft:oak_leaves")));
+            IrisObjectMarker exact = new IrisObjectMarker();
+            exact.setMarker("open");
+            exact.setExact(true);
+            exact.setMark(new KList<>(new IrisBlockData("minecraft:oak_log[axis=y]")));
+            base.setMarkers(new KList<>(loose, exact));
+            for (int rotationIndex = 0; rotationIndex < rotations.size(); rotationIndex++) {
+                IrisObjectPlacement placement = base.toPlacement("marked");
+                placement.setRotation(rotations.get(rotationIndex));
+                for (int seed = 0; seed < 3; seed++) {
+                    RNG rng = new RNG(index * 31L + rotationIndex * 7L + seed);
+                    GoldenPlacer placer = new GoldenPlacer(engine, false);
+                    int result = object.place(100 + index, 80 + seed, 200 - index, placer, placement, rng, null, null, data);
+                    long hash = mix(placer.hash, result);
+                    hash = mix(hash, rng.nextLong());
+                    combined = mix(combined, hash);
+                    markerWrites += placer.markerWrites;
+                }
+            }
+        }
+        assertTrue(markerWrites > 100);
+        assertEquals(Long.toHexString(MARKER_GOLDEN), Long.toHexString(combined));
+    }
+
+    private static long mix(long hash, long value) {
+        long mixed = (hash ^ value) * 0x9E3779B97F4A7C15L;
+        return mixed ^ (mixed >>> 29);
+    }
+
+    private List<IrisObjectRotation> rotations() {
+        IrisObjectRotation defaultY = new IrisObjectRotation();
+        IrisObjectRotation lockedQuarter = IrisObjectRotation.of(0D, 90D, 0D);
+        IrisObjectRotation flipped = rotation(new IrisAxisRotationClamp(true, true, 180D, 180D, 0D),
+                new IrisAxisRotationClamp(true, false, 0D, 0D, 90D), new IrisAxisRotationClamp());
+        IrisObjectRotation angled = rotation(new IrisAxisRotationClamp(true, false, 0D, 0D, 90D),
+                new IrisAxisRotationClamp(true, false, 0D, 0D, 45D), new IrisAxisRotationClamp(true, false, 0D, 0D, 90D));
+        return List.of(defaultY, lockedQuarter, flipped, angled);
+    }
+
+    private IrisObjectPlacement randomPlacement(Random random) {
+        IrisObjectPlacement placement = new IrisObjectPlacement();
+        List<ObjectPlaceMode> modes = List.of(ObjectPlaceMode.CENTER_HEIGHT, ObjectPlaceMode.CENTER_HEIGHT,
+                ObjectPlaceMode.CENTER_HEIGHT, ObjectPlaceMode.STILT, ObjectPlaceMode.FAST_STILT,
+                ObjectPlaceMode.CENTER_STILT, ObjectPlaceMode.ERODE_STILT, ObjectPlaceMode.ORGANIC_STILT,
+                ObjectPlaceMode.CEILING_HANG, ObjectPlaceMode.MAX_HEIGHT, ObjectPlaceMode.FAST_MAX_HEIGHT,
+                ObjectPlaceMode.MIN_HEIGHT, ObjectPlaceMode.PAINT, ObjectPlaceMode.VACUUM, ObjectPlaceMode.VACUUM_ORGANIC,
+                ObjectPlaceMode.STRUCTURE_PIECE, ObjectPlaceMode.FLOATING, ObjectPlaceMode.FAST_MIN_STILT);
+        placement.setMode(modes.get(random.nextInt(modes.size())));
+        if (random.nextInt(4) == 0) {
+            placement.setTranslate(new IrisObjectTranslate()
+                    .setX(random.nextInt(7) - 3)
+                    .setY(random.nextInt(5) - 2)
+                    .setZ(random.nextInt(7) - 3)
+                    .setYRandom(random.nextInt(3) - 1));
+        }
+        if (random.nextInt(6) == 0) {
+            placement.setWarp(new IrisGeneratorStyle(NoiseStyle.SIMPLEX).setMultiplier(1D + random.nextInt(4)));
+        }
+        if (random.nextInt(3) == 0) {
+            placement.setEdit(randomEdits(random));
+        }
+        if (random.nextInt(4) == 0) {
+            placement.setStiltSettings(new IrisStiltSettings());
+        }
+        if (random.nextInt(5) == 0) {
+            placement.setVacuumSettings(new IrisVacuumSettings().setRadius(1 + random.nextInt(4)));
+        }
+        placement.setWaterloggable(random.nextInt(4) == 0);
+        placement.setUnderwater(random.nextInt(8) == 0);
+        placement.setOnwater(random.nextInt(10) == 0);
+        placement.setMeld(random.nextInt(8) == 0);
+        placement.setBore(random.nextInt(10) == 0);
+        placement.setForcePlace(random.nextInt(3) == 0);
+        placement.setBottom(random.nextInt(6) == 0);
+        placement.setSnow(random.nextInt(5) == 0 ? 0.7D : 0D);
+        placement.setRequireSurfaceSupport(random.nextInt(3) != 0);
+        placement.setSurfaceSupportBuffer(random.nextInt(3));
+        placement.setSurfaceSupportDepth(1 + random.nextInt(2));
+        placement.setCarvingSupport(switch (random.nextInt(5)) {
+            case 0 -> CarvingMode.ANYWHERE;
+            case 1 -> CarvingMode.CARVING_ONLY;
+            default -> CarvingMode.SURFACE_ONLY;
+        });
+        return placement;
+    }
+
+    private KList<IrisObjectReplace> randomEdits(Random random) {
+        KList<IrisObjectReplace> edits = new KList<>();
+        int count = 1 + random.nextInt(3);
+        for (int index = 0; index < count; index++) {
+            IrisObjectReplace replace = new IrisObjectReplace();
+            switch (random.nextInt(4)) {
+                case 0 -> {
+                    replace.setFind(new KList<>(new IrisBlockData("minecraft:oak_leaves")));
+                    replace.setReplace(palette("minecraft:cobblestone"));
+                }
+                case 1 -> {
+                    replace.setFind(new KList<>(new IrisBlockData("minecraft:oak_stairs")));
+                    replace.setReplace(palette("minecraft:oak_stairs[half=top]"));
+                }
+                case 2 -> {
+                    replace.setExact(true);
+                    replace.setFind(new KList<>(new IrisBlockData("minecraft:stone")));
+                    replace.setReplace(palette("minecraft:glass"));
+                }
+                default -> {
+                    replace.setFind(new KList<>(new IrisBlockData("minecraft:grass_block"), new IrisBlockData("minecraft:dirt")));
+                    replace.setReplace(palette("minecraft:oak_leaves[distance=2,persistent=false,waterlogged=false]"));
+                }
+            }
+            replace.setChance(switch (random.nextInt(3)) {
+                case 0 -> 1F;
+                case 1 -> 0.5F;
+                default -> 0.15F;
+            });
+            edits.add(replace);
+        }
+        return edits;
+    }
+
+    private static IrisMaterialPalette palette(String key) {
+        IrisMaterialPalette palette = new IrisMaterialPalette();
+        palette.setPalette(new KList<>(new IrisBlockData(key)));
+        return palette;
+    }
+
+    private IrisObject randomObject(Random random, int index) {
+        int width = 1 + random.nextInt(9);
+        int height = 1 + random.nextInt(9);
+        int depth = 1 + random.nextInt(9);
+        IrisObject object = new IrisObject(width, height, depth);
+        int count = 1 + random.nextInt(Math.max(1, (width * height * depth) / 2));
+        List<IrisBlockVector> placed = new ArrayList<>();
+        for (int block = 0; block < count; block++) {
+            int x = random.nextInt(width) - (width / 2);
+            int y = random.nextInt(height) - (height / 2);
+            int z = random.nextInt(depth) - (depth / 2);
+            IrisBlockVector position = new IrisBlockVector(x, y, z);
+            String key = PALETTE.get(random.nextInt(PALETTE.size()));
+            object.getBlocks().put(position, state(key));
+            placed.add(position);
+            if (key.startsWith("minecraft:chest") && random.nextBoolean()) {
+                object.getStates().put(position, new TileData("minecraft:chest", new KMap<>()));
+            }
+        }
+        if (index % 4 == 1 && !placed.isEmpty()) {
+            List<TreeGrounding.Root> roots = new ArrayList<>();
+            Set<TreeBlockCanvas.Vec> canopy = new HashSet<>();
+            for (IrisBlockVector position : placed) {
+                if (random.nextInt(3) == 0) {
+                    canopy.add(new TreeBlockCanvas.Vec(position.getBlockX(), position.getBlockY(), position.getBlockZ()));
+                }
+            }
+            IrisBlockVector root = placed.get(0);
+            roots.add(new TreeGrounding.Root(root.getBlockX(), -(height / 2), root.getBlockZ(), state("minecraft:oak_log[axis=y]")));
+            object.setTreeGrounding(TreeGrounding.create(roots, 4, canopy));
+        }
+        return object;
+    }
+
+    private static IrisObjectRotation rotation(IrisAxisRotationClamp x, IrisAxisRotationClamp y, IrisAxisRotationClamp z) {
+        IrisObjectRotation rotation = new IrisObjectRotation();
+        rotation.setEnabled(true);
+        rotation.setXAxis(x);
+        rotation.setYAxis(y);
+        rotation.setZAxis(z);
+        return rotation;
+    }
+
+    private GoldenState state(String raw) {
+        String key = raw.toLowerCase();
+        if (key.indexOf(':') < 0) {
+            key = "minecraft:" + key;
+        }
+        return states.computeIfAbsent(key, GoldenState::new);
+    }
+
+    private NativeBlockState mergeStates(NativeBlockState base, NativeBlockState update) {
+        GoldenState left = (GoldenState) base;
+        GoldenState right = (GoldenState) update;
+        if (!left.material.equals(right.material)) {
+            return update;
+        }
+        LinkedHashMap<String, String> merged = new LinkedHashMap<>(left.properties);
+        merged.putAll(right.properties);
+        return state(GoldenState.compose(left.material, merged));
+    }
+
+    private static NativeBlockState rotateState(IrisObjectRotation rotation, NativeBlockState state, int spinX, int spinY, int spinZ) {
+        if (state == null || !rotation.canRotate()) {
+            return state;
+        }
+        GoldenState golden = (GoldenState) state;
+        String facing = golden.properties.get("facing");
+        if (facing != null) {
+            IrisBlockVector vector = switch (facing) {
+                case "north" -> new IrisBlockVector(0, 0, -1);
+                case "south" -> new IrisBlockVector(0, 0, 1);
+                case "east" -> new IrisBlockVector(1, 0, 0);
+                case "west" -> new IrisBlockVector(-1, 0, 0);
+                case "up" -> new IrisBlockVector(0, 1, 0);
+                default -> new IrisBlockVector(0, -1, 0);
+            };
+            IrisBlockVector rotated = rotation.rotate(vector, spinX, spinY, spinZ);
+            String face = faceName(rotated);
+            if (face.equals("up") || face.equals("down")) {
+                return golden.material.endsWith("_stairs") ? null : state;
+            }
+            return face.equals(facing) ? state : golden.with("facing", face);
+        }
+        String axis = golden.properties.get("axis");
+        if (axis != null) {
+            IrisBlockVector vector = switch (axis) {
+                case "x" -> new IrisBlockVector(1, 0, 0);
+                case "y" -> new IrisBlockVector(0, 1, 0);
+                default -> new IrisBlockVector(0, 0, 1);
+            };
+            IrisBlockVector rotated = rotation.rotate(vector, spinX, spinY, spinZ);
+            double ax = Math.abs(rotated.getX());
+            double ay = Math.abs(rotated.getY());
+            double az = Math.abs(rotated.getZ());
+            String result = ax >= ay && ax >= az ? "x" : ay >= az ? "y" : "z";
+            return result.equals(axis) ? state : golden.with("axis", result);
+        }
+        return state;
+    }
+
+    private static String faceName(IrisBlockVector vector) {
+        double ax = Math.abs(vector.getX());
+        double ay = Math.abs(vector.getY());
+        double az = Math.abs(vector.getZ());
+        if (ay >= ax && ay >= az) {
+            return vector.getY() > 0 ? "up" : "down";
+        }
+        if (ax >= az) {
+            return vector.getX() > 0 ? "east" : "west";
+        }
+        return vector.getZ() > 0 ? "south" : "north";
+    }
+
+    private final class GoldenState implements NativeBlockState {
+        private final String key;
+        private final String material;
+        private final LinkedHashMap<String, String> properties;
+
+        private GoldenState(String key) {
+            this.key = key;
+            int bracket = key.indexOf('[');
+            this.material = bracket < 0 ? key : key.substring(0, bracket);
+            this.properties = new LinkedHashMap<>();
+            if (bracket >= 0) {
+                for (String part : key.substring(bracket + 1, key.length() - 1).split(",")) {
+                    int split = part.indexOf('=');
+                    properties.put(part.substring(0, split), part.substring(split + 1));
+                }
+            }
+        }
+
+        private static String compose(String material, Map<String, String> properties) {
+            if (properties.isEmpty()) {
+                return material;
+            }
+            StringBuilder builder = new StringBuilder(material).append('[');
+            boolean first = true;
+            for (Map.Entry<String, String> entry : properties.entrySet()) {
+                if (!first) {
+                    builder.append(',');
+                }
+                builder.append(entry.getKey()).append('=').append(entry.getValue());
+                first = false;
+            }
+            return builder.append(']').toString();
+        }
+
+        private GoldenState with(String name, String value) {
+            LinkedHashMap<String, String> updated = new LinkedHashMap<>(properties);
+            updated.put(name, value);
+            return state(compose(material, updated));
+        }
+
+        @Override
+        public String key() {
+            return key;
+        }
+
+        @Override
+        public String namespace() {
+            return "minecraft";
+        }
+
+        @Override
+        public boolean isAir() {
+            return material.endsWith("air");
+        }
+
+        @Override
+        public boolean isSolid() {
+            return !isAir() && !isFluid() && !isVineBlock() && !material.equals("minecraft:lantern");
+        }
+
+        @Override
+        public boolean isOccluding() {
+            return material.equals("minecraft:stone") || material.equals("minecraft:dirt")
+                    || material.equals("minecraft:grass_block") || material.equals("minecraft:oak_log")
+                    || material.equals("minecraft:cobblestone") || material.equals("minecraft:oak_slab");
+        }
+
+        @Override
+        public boolean isCustom() {
+            return false;
+        }
+
+        @Override
+        public boolean isFluid() {
+            return material.equals("minecraft:water");
+        }
+
+        @Override
+        public boolean isWater() {
+            return isFluid();
+        }
+
+        @Override
+        public boolean isWaterLogged() {
+            return "true".equals(properties.get("waterlogged"));
+        }
+
+        @Override
+        public boolean isLit() {
+            return false;
+        }
+
+        @Override
+        public boolean isUpdatable() {
+            return material.endsWith("_stairs");
+        }
+
+        @Override
+        public boolean isFoliage() {
+            return false;
+        }
+
+        @Override
+        public boolean isTreeBlock() {
+            return material.endsWith("_log") || material.endsWith("_leaves");
+        }
+
+        @Override
+        public boolean isFoliagePlantable() {
+            return material.equals("minecraft:grass_block") || material.equals("minecraft:dirt");
+        }
+
+        @Override
+        public boolean isDecorant() {
+            return false;
+        }
+
+        @Override
+        public boolean isStorage() {
+            return material.equals("minecraft:chest");
+        }
+
+        @Override
+        public boolean isStorageChest() {
+            return isStorage();
+        }
+
+        @Override
+        public boolean isOre() {
+            return false;
+        }
+
+        @Override
+        public boolean isDeepSlate() {
+            return false;
+        }
+
+        @Override
+        public boolean isVineBlock() {
+            return material.equals("minecraft:vine");
+        }
+
+        @Override
+        public boolean canPlaceOnto(NativeBlockState onto) {
+            return onto != null && onto.isSolid();
+        }
+
+        @Override
+        public boolean matches(NativeBlockState state) {
+            if (!(state instanceof GoldenState other) || !other.material.equals(material)) {
+                return false;
+            }
+            for (Map.Entry<String, String> entry : other.properties.entrySet()) {
+                if (!entry.getValue().equals(properties.get(entry.getKey()))) {
+                    return false;
+                }
+            }
+            return true;
+        }
+
+        @Override
+        public boolean hasTileEntity() {
+            return isStorage();
+        }
+
+        @Override
+        public NativeBlockState withProperty(String name, String value) {
+            return with(name, value);
+        }
+
+        @Override
+        public Object nativeHandle() {
+            return key;
+        }
+
+        @Override
+        public String toString() {
+            return key;
+        }
+    }
+
+    private final class GoldenPlacer implements IObjectPlacer {
+        private final Engine engine;
+        private final boolean preventDecay;
+        private final Map<Long, NativeBlockState> blocks = new HashMap<>();
+        private final Map<Long, Map<Class<?>, Object>> extra = new HashMap<>();
+        private long hash = 31L;
+        private int writes;
+        private int markerWrites;
+
+        private GoldenPlacer(Engine engine, boolean preventDecay) {
+            this.engine = engine;
+            this.preventDecay = preventDecay;
+        }
+
+        private static long key(int x, int y, int z) {
+            return (((long) x & 0x3FFFFFL) << 42) | (((long) y & 0xFFFFFL) << 22) | ((long) z & 0x3FFFFFL);
+        }
+
+        private int surface(int x, int z) {
+            return 64 + Math.floorMod(x * 31 + z * 17, 9) - 4;
+        }
+
+        private void record(String kind, int x, int y, int z, String value) {
+            writes++;
+            hash = mix(hash, kind.hashCode());
+            hash = mix(hash, x);
+            hash = mix(hash, y);
+            hash = mix(hash, z);
+            hash = mix(hash, value.hashCode());
+        }
+
+        @Override
+        public int getHighest(int x, int z, IrisData data) {
+            return surface(x, z);
+        }
+
+        @Override
+        public int getHighest(int x, int z, IrisData data, boolean ignoreFluid) {
+            return ignoreFluid ? surface(x, z) : Math.max(surface(x, z), 62);
+        }
+
+        @Override
+        public void set(int x, int y, int z, NativeBlockState d) {
+            record("set", x, y, z, d == null ? "null" : d.key());
+            blocks.put(key(x, y, z), d);
+        }
+
+        @Override
+        public NativeBlockState get(int x, int y, int z) {
+            NativeBlockState written = blocks.get(key(x, y, z));
+            if (written != null) {
+                return written;
+            }
+            int surface = surface(x, z);
+            if (y <= surface) {
+                return state(y == surface ? "minecraft:grass_block[snowy=false]" : "minecraft:stone");
+            }
+            if (y <= 62) {
+                return state("minecraft:water");
+            }
+            return Math.floorMod(x + y + z, 13) == 0 ? state("minecraft:oak_leaves[distance=1,persistent=true,waterlogged=true]") : null;
+        }
+
+        @Override
+        public boolean isPreventingDecay() {
+            return preventDecay;
+        }
+
+        @Override
+        public boolean isCarved(int x, int y, int z) {
+            return Math.floorMod(x * 7 + y * 3 + z * 11, 29) == 0;
+        }
+
+        @Override
+        public boolean isSolid(int x, int y, int z) {
+            NativeBlockState state = get(x, y, z);
+            return state != null && state.isSolid();
+        }
+
+        @Override
+        public boolean isUnderwater(int x, int z) {
+            return surface(x, z) < 62;
+        }
+
+        @Override
+        public int getFluidHeight() {
+            return 62;
+        }
+
+        @Override
+        public int getFluidHeight(int x, int z) {
+            return 62;
+        }
+
+        @Override
+        public boolean isDebugSmartBore() {
+            return false;
+        }
+
+        @Override
+        public void setTile(int xx, int yy, int zz, TileData tile) {
+            record("tile", xx, yy, zz, tile == null ? "null" : "tile");
+        }
+
+        @Override
+        public <T> void setData(int xx, int yy, int zz, T value) {
+            record("data", xx, yy, zz, value == null ? "null" : value.getClass().getSimpleName() + ":" + value);
+            if (value instanceof MatterMarker) {
+                markerWrites++;
+            }
+            extra.computeIfAbsent(key(xx, yy, zz), ignored -> new HashMap<>()).put(value == null ? Object.class : value.getClass(), value);
+        }
+
+        @Override
+        public <T> T getData(int xx, int yy, int zz, Class<T> type) {
+            Map<Class<?>, Object> values = extra.get(key(xx, yy, zz));
+            Object value = values == null ? null : values.get(type);
+            return value == null ? null : type.cast(value);
+        }
+
+        @Override
+        public boolean beginTreeCanopy(BlockPosition position) {
+            boolean open = IObjectPlacer.super.beginTreeCanopy(position);
+            record("canopy", position.getX(), position.getY(), position.getZ(), Boolean.toString(open));
+            return open;
+        }
+
+        @Override
+        public Engine getEngine() {
+            return engine;
+        }
+    }
+}
diff --git a/probe/src/main/java/art/arcane/iris/probe/GenerationProbe.java b/probe/src/main/java/art/arcane/iris/probe/GenerationProbe.java
index bdd819bba..81b78ae28 100644
--- a/probe/src/main/java/art/arcane/iris/probe/GenerationProbe.java
+++ b/probe/src/main/java/art/arcane/iris/probe/GenerationProbe.java
@@ -18,6 +18,8 @@
 
 package art.arcane.iris.probe;
 
+import art.arcane.iris.generation.bake.BakePlane;
+import art.arcane.iris.generation.bake.GeneratorEvaluations;
 import art.arcane.iris.generation.mantle.IrisCaveCarver3D;
 import art.arcane.iris.pack.datapack.DataVersion;
 import art.arcane.iris.pack.loading.IrisData;
@@ -622,9 +624,11 @@ public final class GenerationProbe {
         int totalChunks = coordinates.size();
         long measuredStartEpochMillis = 0L;
         ProbeWindowMetrics measuredStart = null;
+        GeneratorEvaluations.Snapshot measuredStartEvaluations = GeneratorEvaluations.snapshot();
         for (int index = 0; index < totalChunks; index++) {
             if (index == configuration.warmupChunks()) {
                 measuredStartEpochMillis = System.currentTimeMillis();
+                measuredStartEvaluations = GeneratorEvaluations.snapshot();
                 measuredStart = ProbeWindowMetrics.capture(generator.engine(), options.counters());
             }
             drainReported();
@@ -633,7 +637,7 @@ public final class GenerationProbe {
             sink.accept(outcome, index >= configuration.warmupChunks());
             printProgress(configuration, index + 1, totalChunks);
         }
-        printWindow(measuredStartEpochMillis, System.currentTimeMillis());
+        printWindow(generator.engine(), measuredStartEpochMillis, System.currentTimeMillis(), measuredStartEvaluations);
         printWindowMetrics(measuredStart, ProbeWindowMetrics.capture(generator.engine(), options.counters()),
                 configuration.measuredChunks(), options);
     }
@@ -646,9 +650,19 @@ public final class GenerationProbe {
         }
     }
 
-    private static void printWindow(long startEpochMillis, long endEpochMillis) {
+    private static void printWindow(Engine engine, long startEpochMillis, long endEpochMillis, GeneratorEvaluations.Snapshot startEvaluations) {
         System.out.println("IRIS_GENPROBE_WINDOW phase=measured start_epoch_ms=" + startEpochMillis
                 + " end_epoch_ms=" + endEpochMillis);
+        GeneratorEvaluations.Snapshot evaluations = GeneratorEvaluations.snapshot().minus(startEvaluations);
+        System.out.printf(Locale.ROOT, "IRIS_GENPROBE_GENERATORS baked_chunks=%d baked_evaluations=%d evaluations_per_baked_chunk=%.3f batched_evaluations=%d scalar_evaluations=%d%n",
+                evaluations.bakedChunks(), evaluations.bakedEvaluations(), evaluations.bakedEvaluationsPerChunk(),
+                evaluations.batchedEvaluations(), evaluations.scalarEvaluations());
+        long[] census = engine.getComplex().bakeCensus();
+        StringBuilder planes = new StringBuilder("IRIS_GENPROBE_BAKE entries=").append(census[BakePlane.values().length]);
+        for (BakePlane plane : BakePlane.values()) {
+            planes.append(' ').append(plane.name().toLowerCase(Locale.ROOT)).append('=').append(census[plane.ordinal()]);
+        }
+        System.out.println(planes);
     }
 
     private static void generateParallel(ProbeChunkGenerator generator, ProbeConfiguration configuration,
@@ -676,10 +690,11 @@ public final class GenerationProbe {
                     configuration.centerChunkX(), configuration.centerChunkZ());
             ProbeWindowMetrics measuredStart = ProbeWindowMetrics.capture(generator.engine(), options.counters());
             long measuredStartEpochMillis = System.currentTimeMillis();
+            GeneratorEvaluations.Snapshot measuredStartEvaluations = GeneratorEvaluations.snapshot();
             long measuredStarted = System.nanoTime();
             runPhase(executor, generator, configuration, coordinates, measured, outcomes);
             measuredWallNanos = System.nanoTime() - measuredStarted;
-            printWindow(measuredStartEpochMillis, System.currentTimeMillis());
+            printWindow(generator.engine(), measuredStartEpochMillis, System.currentTimeMillis(), measuredStartEvaluations);
             printWindowMetrics(measuredStart, ProbeWindowMetrics.capture(generator.engine(), options.counters()),
                     configuration.measuredChunks(), options);
             unattributed.addAll(drainReported());