diff --git a/GlitchyEngine/src/Scripting/ScriptEngine.bf b/GlitchyEngine/src/Scripting/ScriptEngine.bf
index c8d84b1..87f78b4 100644
--- a/GlitchyEngine/src/Scripting/ScriptEngine.bf
+++ b/GlitchyEngine/src/Scripting/ScriptEngine.bf
@@ -859,11 +859,17 @@ static class ScriptEngine
 
 		for (let (id, script) in _entityScriptInstances)
 		{
-			SerializedObject object = new SerializedObject(allObjects, script.ScriptClass.FullName, script.EntityId);
-			object.Serialize(script);
+			SerializeScriptInstance(script, allObjects);
 		}
 	}
 
+	/// Serializes the given script instance
+	public static void SerializeScriptInstance(ScriptInstance script, Dictionary<UUID, SerializedObject> allObjects)
+	{
+		SerializedObject object = new SerializedObject(allObjects, script.ScriptClass.FullName, script.EntityId);
+		object.Serialize(script);
+	}
+
 	/// Deserializes the given data into the script instances
 	public static void DeserializeScriptInstances(Dictionary<UUID, SerializedObject> allObjects)
 	{
@@ -871,9 +877,36 @@ static class ScriptEngine
 
 		for (let (id, script) in _entityScriptInstances)
 		{
-			if (allObjects.TryGetValue(id, let object))
+			DeserializeScriptInstance(id, script, allObjects);
+		}
+	}
+	
+	/// Deserializes the given script instance.
+	/// @returns true if the script had serialized data; false otherwise.
+	public static bool DeserializeScriptInstance(UUID id, ScriptInstance script, Dictionary<UUID, SerializedObject> allObjects)
+	{
+		if (allObjects.TryGetValue(id, let object))
+		{
+			object.Deserialize(script);
+
+			return true;
+		}
+
+		return false;
+	}
+
+	/// Replaces Entity references in the given serialized data using the specified translation table.
+	public static void FixupSerializedIds(Dictionary<UUID, UUID> originalToCopyIds, Dictionary<UUID, SerializedObject> allObjects)
+	{
+		for (let (id, object) in allObjects)
+		{
+			for (var fieldData in ref object.Fields.Values)
 			{
-				object.Deserialize(script);
+				if (fieldData.PrimitiveType != .EntityReference && fieldData.PrimitiveType != .ComponentReference)
+					continue;
+
+				if (originalToCopyIds.TryGetValue(fieldData.Data.EngineObject.ID, let copyId))
+					fieldData.Data.EngineObject.ID = copyId;
 			}
 		}
 	}
diff --git a/GlitchyEngine/src/World/Scene.bf b/GlitchyEngine/src/World/Scene.bf
index 1908377..ad8e643 100644
--- a/GlitchyEngine/src/World/Scene.bf
+++ b/GlitchyEngine/src/World/Scene.bf
@@ -8,6 +8,7 @@ using GlitchyEngine.Content;
 using GlitchyEngine.Scripting;
 using GlitchyEngine.Math;
 using GlitchyEngine.Scripting.Classes;
+using GlitchyEngine.Serialization;
 
 namespace GlitchyEngine.World
 {
@@ -773,10 +774,14 @@ namespace GlitchyEngine.World
 		 */
 		public Entity CreateInstance(Entity entity)
 		{
+			Dictionary<UUID, SerializedObject> serializedData = scope .();
+			defer { ClearDictionaryAndDeleteValues!(serializedData); }
+
 			List<Entity> newEntities = scope .();
 			Dictionary<EcsEntity, EcsEntity> sourceToTargetEntity = scope .();
 			Dictionary<UUID, UUID> sourceIdToTargetId = scope .();
 			Dictionary<UUID, Entity> targetIdToSourceEntity = scope .();
+			List<(UUID oldId, ScriptInstance scriptInstance)> newScripts = scope .();
 			
 			Entity CopyEntityAndChildren(Entity original, Entity? copyParent)
 			{
@@ -801,7 +806,7 @@ namespace GlitchyEngine.World
 				CopyComponent<BoxCollider2DComponent>(original, copy);
 				CopyComponent<CircleCollider2DComponent>(original, copy);
 				CopyComponent<PolygonCollider2DComponent>(original, copy);
-				
+
 				// Copy ScriptComponent... needs extra handling for the script instances
 				if (original.TryGetComponent<ScriptComponent>(let sourceScript))
 				{
@@ -809,15 +814,16 @@ namespace GlitchyEngine.World
 					
 					targetScript.ScriptClassName = sourceScript.ScriptClassName;
 
-					// Initializes the created instance
-					// TODO: this returns false, if no script with ScriptClassName exists, we have to handle this case correctly I think.
-					ScriptEngine.InitializeInstance(copy, targetScript);
-
-					// TODO: Copy Data from one instance to another
-					//ScriptEngine.CopyFieldsToInstance(targetScript, sourceScript);
-
-					// TODO: Only if we are in Runtime
-					targetScript.Instance.InvokeOnCreate();
+					if (sourceScript.Instance != null)
+					{
+						ScriptEngine.SerializeScriptInstance(sourceScript.Instance, serializedData);
+						
+						// Initializes the created instance
+						// TODO: this returns false, if no script with ScriptClassName exists, we have to handle this case correctly I think.
+						ScriptEngine.InitializeInstance(copy, targetScript);
+						
+						newScripts.Add((original.UUID, targetScript.Instance));
+					}
 				}
 
 				// This is kinda slow because it's in O(n*m) where n is the tree depth and m is the total number of entities in the scene...
@@ -830,22 +836,22 @@ namespace GlitchyEngine.World
 			}
 
 			Entity newEntity = CopyEntityAndChildren(entity, null);
-			
-			for (let copy in newEntities)
+
+			// Replace old IDs with new ones
+			ScriptEngine.FixupSerializedIds(sourceIdToTargetId, serializedData);
+
+			// Use separate loops for deserialization and OnCreate to ensure complete entities and references in OnCreate
+
+			for (let (originalId, newScriptInstance) in newScripts)
 			{
-				if (copy.TryGetComponent<ScriptComponent>(let targetScript))
-				{
-					Entity originalEntity = targetIdToSourceEntity[copy.UUID];
-
-					if (!originalEntity.TryGetComponent<ScriptComponent>(let sourceScript))
-						continue;
-
-					ScriptEngine.CopyFieldsToInstance(targetScript, sourceScript, sourceIdToTargetId);
-
-					//targetScript.Instance.InvokeOnCreate();
-				}
+				ScriptEngine.DeserializeScriptInstance(originalId, newScriptInstance, serializedData);
 			}
 
+			for (let (_, newScriptInstance) in newScripts)
+			{
+				if (ScriptEngine.ApplicationInfo.IsInPlayMode || newScriptInstance.ScriptClass.RunInEditMode)
+					newScriptInstance.InvokeOnCreate();
+			}
 
 			return newEntity;
 		}
diff --git a/ScriptCore/Serialization/DeserializationObject.cs b/ScriptCore/Serialization/DeserializationObject.cs
index 852c935..019526b 100644
--- a/ScriptCore/Serialization/DeserializationObject.cs
+++ b/ScriptCore/Serialization/DeserializationObject.cs
@@ -504,7 +504,7 @@ public class DeserializationObject
 
     public unsafe object? DeserializeClass(string fieldName, Type fieldType)
     {
-        if (fieldType.GetGenericTypeDefinition() == typeof(List<>))
+        if (fieldType.IsGenericType && fieldType.GetGenericTypeDefinition() == typeof(List<>))
         {
             return DeserializeList(fieldName, fieldType, fieldType.GetGenericArguments()[0]);
         }
@@ -514,7 +514,10 @@ public class DeserializationObject
 
         if (isEntity || isComponent)
         {
-            var data = (DataHelper.EngineObjectReferenceHelper)GetFieldValue(fieldName, isEntity ? SerializationType.EntityReference : SerializationType.ComponentReference);
+            object? fieldData = GetFieldValue(fieldName, isEntity ? SerializationType.EntityReference : SerializationType.ComponentReference);
+
+            if (fieldData is not DataHelper.EngineObjectReferenceHelper data)
+                return NoValueDeserialized;
 
             UUID id = data.Id;