diff --git a/common/implementation/src/main/java/com/dfsek/terra/config/pack/ConfigPackImpl.java b/common/implementation/src/main/java/com/dfsek/terra/config/pack/ConfigPackImpl.java
index 6c96d491c..2da842a0f 100644
--- a/common/implementation/src/main/java/com/dfsek/terra/config/pack/ConfigPackImpl.java
+++ b/common/implementation/src/main/java/com/dfsek/terra/config/pack/ConfigPackImpl.java
@@ -82,22 +82,18 @@ public class ConfigPackImpl implements ConfigPack {
 
     private final BiomeProviderBuilder biomeProviderBuilder;
 
+    private final Map<Class<?>, ImmutablePair<OpenRegistry<?>, CheckedRegistry<?>>> registryMap = new HashMap<>();
 
     private final ConfigTypeRegistry configTypeRegistry;
-    private final Map<Class<?>, ImmutablePair<OpenRegistry<?>, CheckedRegistry<?>>> registryMap = new HashMap<>();
+
 
     private final TreeMap<Integer, List<ImmutablePair<String, ConfigType<?, ?>>>> configTypes = new TreeMap<>();
 
     public ConfigPackImpl(File folder, TerraPlugin main) throws ConfigException {
         try {
-            this.configTypeRegistry = new ConfigTypeRegistry(main, (id, configType) -> {
-                OpenRegistry<?> openRegistry = configType.registrySupplier().get();
-                selfLoader.registerLoader(configType.getTypeClass(), openRegistry);
-                abstractConfigLoader.registerLoader(configType.getTypeClass(), openRegistry);
-                registryMap.put(configType.getTypeClass(), ImmutablePair.of(openRegistry, new CheckedRegistryImpl<>(openRegistry)));
-            });
             this.loader = new FolderLoader(folder.toPath());
             this.main = main;
+            this.configTypeRegistry = createRegistry();
             long l = System.nanoTime();
 
             register(abstractConfigLoader);
@@ -139,14 +135,9 @@ public class ConfigPackImpl implements ConfigPack {
 
     public ConfigPackImpl(ZipFile file, TerraPlugin main) throws ConfigException {
         try {
-            this.configTypeRegistry = new ConfigTypeRegistry(main, (id, configType) -> {
-                OpenRegistry<?> openRegistry = configType.registrySupplier().get();
-                selfLoader.registerLoader(configType.getTypeClass(), openRegistry);
-                abstractConfigLoader.registerLoader(configType.getTypeClass(), openRegistry);
-                registryMap.put(configType.getTypeClass(), ImmutablePair.of(openRegistry, new CheckedRegistryImpl<>(openRegistry)));
-            });
             this.loader = new ZIPLoader(file);
             this.main = main;
+            this.configTypeRegistry = createRegistry();
             long l = System.nanoTime();
 
             register(selfLoader);
@@ -196,6 +187,19 @@ public class ConfigPackImpl implements ConfigPack {
         toWorldConfig(new TerraWorldImpl(new DummyWorld(), this, main)); // Build now to catch any errors immediately.
     }
 
+    private ConfigTypeRegistry createRegistry() {
+        return new ConfigTypeRegistry(main, (id, configType) -> {
+            OpenRegistry<?> openRegistry = configType.registrySupplier().get();
+            if(registryMap.containsKey(configType.getTypeClass())) { // Someone already registered something; we need to copy things to the new registry.
+                //noinspection unchecked
+                registryMap.get(configType.getTypeClass()).getLeft().forEach(((OpenRegistry<Object>) openRegistry)::register);
+            }
+            selfLoader.registerLoader(configType.getTypeClass(), openRegistry);
+            abstractConfigLoader.registerLoader(configType.getTypeClass(), openRegistry);
+            registryMap.put(configType.getTypeClass(), ImmutablePair.of(openRegistry, new CheckedRegistryImpl<>(openRegistry)));
+        });
+    }
+
     private void checkDeadEntries(TerraPlugin main) {
         registryMap.forEach((clazz, pair) -> ((OpenRegistryImpl<?>) pair.getLeft()).getDeadEntries().forEach((id, value) -> main.getDebugLogger().warning("Dead entry in '" + clazz + "' registry: '" + id + "'")));
     }
diff --git a/common/implementation/src/main/java/com/dfsek/terra/registry/OpenRegistryImpl.java b/common/implementation/src/main/java/com/dfsek/terra/registry/OpenRegistryImpl.java
index 3b551e391..9c2608057 100644
--- a/common/implementation/src/main/java/com/dfsek/terra/registry/OpenRegistryImpl.java
+++ b/common/implementation/src/main/java/com/dfsek/terra/registry/OpenRegistryImpl.java
@@ -6,7 +6,6 @@ import com.dfsek.terra.api.registry.OpenRegistry;
 import com.dfsek.terra.api.registry.exception.DuplicateEntryException;
 
 import java.lang.reflect.AnnotatedType;
-import java.lang.reflect.Type;
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;
@@ -47,10 +46,10 @@ public class OpenRegistryImpl<T> implements OpenRegistry<T> {
 
     @Override
     public boolean register(String identifier, T value) {
-        return add(identifier, new Entry<>(value));
+        return register(identifier, new Entry<>(value));
     }
 
-    public boolean add(String identifier, Entry<T> value) {
+    public boolean register(String identifier, Entry<T> value) {
         boolean exists = objects.containsKey(identifier);
         objects.put(identifier, value);
         return exists;
diff --git a/common/implementation/src/main/java/com/dfsek/terra/registry/config/ConfigTypeRegistry.java b/common/implementation/src/main/java/com/dfsek/terra/registry/config/ConfigTypeRegistry.java
index 9963508bb..eb48c2639 100644
--- a/common/implementation/src/main/java/com/dfsek/terra/registry/config/ConfigTypeRegistry.java
+++ b/common/implementation/src/main/java/com/dfsek/terra/registry/config/ConfigTypeRegistry.java
@@ -19,9 +19,9 @@ public class ConfigTypeRegistry extends OpenRegistryImpl<ConfigType<?, ?>> {
     }
 
     @Override
-    public boolean add(String identifier, Entry<ConfigType<?, ?>> value) {
+    public boolean register(String identifier, Entry<ConfigType<?, ?>> value) {
         callback.accept(identifier, value.getValue());
         main.getDebugLogger().info("Registered config registry with ID " + identifier + " to class " + value.getValue().getTypeClass().getCanonicalName());
-        return super.add(identifier, value);
+        return super.register(identifier, value);
     }
 }
diff --git a/common/implementation/src/main/java/com/dfsek/terra/registry/master/AddonRegistry.java b/common/implementation/src/main/java/com/dfsek/terra/registry/master/AddonRegistry.java
index 0aba01392..1965c5792 100644
--- a/common/implementation/src/main/java/com/dfsek/terra/registry/master/AddonRegistry.java
+++ b/common/implementation/src/main/java/com/dfsek/terra/registry/master/AddonRegistry.java
@@ -34,7 +34,7 @@ public class AddonRegistry extends OpenRegistryImpl<TerraAddon> {
     public boolean register(String identifier, TerraAddon addon) {
         if(contains(identifier)) throw new IllegalArgumentException("Addon " + identifier + " is already registered.");
         addon.initialize();
-        main.logger().info("Loaded com.dfsek.terra.addon " + addon.getName() + " v" + addon.getVersion() + ", by " + addon.getAuthor());
+        main.logger().info("Loaded addon " + addon.getName() + " v" + addon.getVersion() + ", by " + addon.getAuthor());
         return super.register(identifier, addon);
     }
 
@@ -44,6 +44,9 @@ public class AddonRegistry extends OpenRegistryImpl<TerraAddon> {
     }
 
     public boolean loadAll() {
+        return loadAll(TerraPlugin.class.getClassLoader());
+    }
+    public boolean loadAll(ClassLoader parent) {
         InjectorImpl<TerraPlugin> pluginInjector = new InjectorImpl<>(main);
         pluginInjector.addExplicitTarget(TerraPlugin.class);
 
@@ -56,7 +59,7 @@ public class AddonRegistry extends OpenRegistryImpl<TerraAddon> {
         try {
             for(File jar : addonsFolder.listFiles(file -> file.getName().endsWith(".jar"))) {
                 main.logger().info("Loading Addon(s) from: " + jar.getName());
-                for(Class<? extends TerraAddon> addonClass : AddonClassLoader.fetchAddonClasses(jar)) {
+                for(Class<? extends TerraAddon> addonClass : AddonClassLoader.fetchAddonClasses(jar, parent)) {
                     pool.add(new PreLoadAddon(addonClass, jar));
                 }
             }
diff --git a/common/loader/addon/src/main/java/com/dfsek/terra/addon/AddonClassLoader.java b/common/loader/addon/src/main/java/com/dfsek/terra/addon/AddonClassLoader.java
index e4258ba31..93631de6f 100644
--- a/common/loader/addon/src/main/java/com/dfsek/terra/addon/AddonClassLoader.java
+++ b/common/loader/addon/src/main/java/com/dfsek/terra/addon/AddonClassLoader.java
@@ -27,35 +27,36 @@ public class AddonClassLoader extends URLClassLoader {
     }
 
     @SuppressWarnings("unchecked")
-    public static Set<Class<? extends TerraAddon>> fetchAddonClasses(File file) throws IOException {
+    public static Set<Class<? extends TerraAddon>> fetchAddonClasses(File file, ClassLoader parent) throws IOException {
         JarFile jarFile = new JarFile(file);
         Enumeration<JarEntry> entries = jarFile.entries();
 
-        AddonClassLoader loader = new AddonClassLoader(new URL[] {file.toURI().toURL()}, AddonClassLoader.class.getClassLoader());
+        try(AddonClassLoader loader = new AddonClassLoader(new URL[] {file.toURI().toURL()}, parent)) {
 
-        Set<Class<? extends TerraAddon>> set = new HashSet<>();
-        while(entries.hasMoreElements()) {
-            JarEntry entry = entries.nextElement();
+            Set<Class<? extends TerraAddon>> set = new HashSet<>();
+            while(entries.hasMoreElements()) {
+                JarEntry entry = entries.nextElement();
 
-            if(entry.isDirectory() || !entry.getName().endsWith(".class")) continue;
-            String className = entry.getName().substring(0, entry.getName().length() - 6).replace('/', '.');
+                if(entry.isDirectory() || !entry.getName().endsWith(".class")) continue;
+                String className = entry.getName().substring(0, entry.getName().length() - 6).replace('/', '.');
 
-            try {
-                Class<?> clazz = loader.loadClass(className);
+                try {
+                    Class<?> clazz = loader.loadClass(className);
 
-                Addon addon = clazz.getAnnotation(Addon.class);
+                    Addon addon = clazz.getAnnotation(Addon.class);
 
-                if(addon == null) continue;
+                    if(addon == null) continue;
 
-                if(!TerraAddon.class.isAssignableFrom(clazz))
-                    throw new IllegalArgumentException("Addon class \"" + clazz + "\" must extend TerraAddon.");
+                    if(!TerraAddon.class.isAssignableFrom(clazz))
+                        throw new IllegalArgumentException("Addon class \"" + clazz + "\" must extend TerraAddon.");
 
-                set.add((Class<? extends TerraAddon>) clazz);
-            } catch(ClassNotFoundException e) {
-                throw new IllegalStateException(e); // this should literally never happen, if it does something is very wrong
+                    set.add((Class<? extends TerraAddon>) clazz);
+                } catch(ClassNotFoundException e) {
+                    throw new IllegalStateException(e); // this should literally never happen, if it does something is very wrong
+                }
             }
-        }
 
-        return set;
+            return set;
+        }
     }
 }
diff --git a/common/loader/addon/src/main/java/com/dfsek/terra/addon/PreLoadAddon.java b/common/loader/addon/src/main/java/com/dfsek/terra/addon/PreLoadAddon.java
index 379ca5e35..f3b1b0482 100644
--- a/common/loader/addon/src/main/java/com/dfsek/terra/addon/PreLoadAddon.java
+++ b/common/loader/addon/src/main/java/com/dfsek/terra/addon/PreLoadAddon.java
@@ -33,7 +33,7 @@ public class PreLoadAddon {
 
     public void rebuildDependencies(AddonPool pool, PreLoadAddon origin, boolean levelG1) throws AddonLoadException {
         if(this.equals(origin) && !levelG1)
-            throw new CircularDependencyException("Detected circular dependency in com.dfsek.terra.addon \"" + id + "\", dependencies: " + Arrays.toString(dependencies));
+            throw new CircularDependencyException("Detected circular dependency in addon \"" + id + "\", dependencies: " + Arrays.toString(dependencies));
 
         for(String dependency : dependencies) {
             PreLoadAddon preLoadAddon = pool.get(dependency);
diff --git a/platforms/fabric/src/main/java/com/dfsek/terra/fabric/TerraFabricPlugin.java b/platforms/fabric/src/main/java/com/dfsek/terra/fabric/TerraFabricPlugin.java
index 6784991d5..7a7e692e2 100644
--- a/platforms/fabric/src/main/java/com/dfsek/terra/fabric/TerraFabricPlugin.java
+++ b/platforms/fabric/src/main/java/com/dfsek/terra/fabric/TerraFabricPlugin.java
@@ -260,7 +260,7 @@ public class TerraFabricPlugin implements TerraPlugin, ModInitializer {
         debugLogger.setDebug(config.isDebugLogging());
         if(config.isDebugProfiler()) profiler.start();
 
-        if(!addonRegistry.loadAll()) {
+        if(!addonRegistry.loadAll(getClass().getClassLoader())) {
             throw new IllegalStateException("Failed to load addons. Please correct com.dfsek.terra.addon installations to continue.");
         }
         logger.info("Loaded addons.");
@@ -317,10 +317,10 @@ public class TerraFabricPlugin implements TerraPlugin, ModInitializer {
             eventManager.registerListener(this, this);
         }
 
-        @Priority(Priority.LOWEST)
+        @Priority(Priority.HIGHEST)
         @Global
         public void injectTrees(ConfigPackPreLoadEvent event) {
-            CheckedRegistry<Tree> treeRegistry = event.getPack().getCheckedRegistry(Tree.class);
+            CheckedRegistry<Tree> treeRegistry = event.getPack().getOrCreateRegistry(Tree.class);
             injectTree(treeRegistry, "BROWN_MUSHROOM", ConfiguredFeatures.HUGE_BROWN_MUSHROOM);
             injectTree(treeRegistry, "RED_MUSHROOM", ConfiguredFeatures.HUGE_RED_MUSHROOM);
             injectTree(treeRegistry, "JUNGLE", ConfiguredFeatures.MEGA_JUNGLE_TREE);