diff --git a/Editor/ClusterView.cs b/Editor/ClusterView.cs
index e9d147f..5c53682 100644
--- a/Editor/ClusterView.cs
+++ b/Editor/ClusterView.cs
@@ -103,6 +103,8 @@ namespace NanoBrain.Unity {
         public Nucleus currentNucleus = null;
         public Nucleus selectedSynapseNeuron = null;
         public Nucleus selectedOutput;
+        public bool isOpen = true;
+        public bool initialized;
 
         #region Focus Graph
 
diff --git a/Editor/Cluster_Drawer.cs b/Editor/Cluster_Drawer.cs
index 989d774..79e9037 100644
--- a/Editor/Cluster_Drawer.cs
+++ b/Editor/Cluster_Drawer.cs
@@ -1,12 +1,9 @@
-using System.Linq;
 using System.Collections;
 using System.Collections.Generic;
 using System.Reflection;
 using UnityEngine;
-using UnityEngine.UIElements;
 using UnityEditor;
 using System;
-using System.Reflection;
 
 namespace NanoBrain.Unity {
 
@@ -15,7 +12,16 @@ namespace NanoBrain.Unity {
 
         static Cluster_Drawer() {
             SceneView.duringSceneGui += OnSceneGUI;
+            Selection.selectionChanged += OnSelectionChanged;
+            if (clusterView != null)
+                clusterView.initialized = false;
         }
+        ~Cluster_Drawer() {
+            SceneView.duringSceneGui -= OnSceneGUI;
+        }
+
+        //static readonly Dictionary<string, bool> s_foldouts = new();
+        static readonly Dictionary<string, ClusterView> clusterViews = new();
 
         public static void Insepctor(SerializedObject serializedObject, string propertyName) {
             EditorGUILayout.PropertyField(serializedObject.FindProperty(propertyName));
@@ -26,12 +32,24 @@ namespace NanoBrain.Unity {
         private static ClusterView clusterView;
         private static UnityEngine.Object selectedTarget;
 
+        public ClusterView GetClusterView(SerializedProperty property) {
+            string key = property.propertyPath + "_" + property.serializedObject.targetObject.GetInstanceID();//GetEntityId();
+            if (clusterViews.TryGetValue(key, out ClusterView view))
+                return view;
+
+            view = new ClusterView();
+            clusterViews[key] = view;
+            return view;
+        }
+
         public override float GetPropertyHeight(SerializedProperty property, GUIContent label) {
             float height = EditorGUIUtility.singleLineHeight + padding;
-            string key = property.propertyPath + "_" + property.serializedObject.targetObject.GetInstanceID();//GetEntityId();
-            s_foldouts.TryGetValue(key, out bool isOpen);
+            // string key = property.propertyPath + "_" + property.serializedObject.targetObject.GetInstanceID();//GetEntityId();
+            // //s_foldouts.TryGetValue(key, out bool isOpen);
+            // clusterViews.TryGetValue(key, out ClusterView view);
+            ClusterView view = GetClusterView(property);
             SerializedProperty prefabProp = property.FindPropertyRelative(nameof(Cluster.prefab));
-            if (prefabProp.objectReferenceValue != null && isOpen) {
+            if (prefabProp.objectReferenceValue != null && view.isOpen) {
                 height += padding + elementHeight;
                 height = 500;
             }
@@ -40,9 +58,10 @@ namespace NanoBrain.Unity {
             return height;
         }
 
-        static readonly Dictionary<string, bool> s_foldouts = new();
 
         public override void OnGUI(Rect position, SerializedProperty property, GUIContent label) {
+            ClusterView clusterView = GetClusterView(property);
+
             label = EditorGUI.BeginProperty(position, label, property);
 
             // Begin indent block
@@ -73,27 +92,40 @@ namespace NanoBrain.Unity {
             }
 
             if (prefabProp.objectReferenceValue is ClusterPrefab prefab) {
+                // // Graph is not shown when multi-editing
                 if (property.serializedObject.targetObjects.Length == 1) {
-                    // Graph is not shown when multi-editing
                     UnityEngine.Object targetObject = property.serializedObject.targetObject;
                     Cluster_Drawer.selectedTarget = targetObject;
-                    Cluster cluster = SerializedPropertyUtility.GetManagedObjectForProperty(targetObject, property.propertyPath) as Cluster;
+
+                    Cluster cluster;
+                    if (clusterView.initialized) {
+                        cluster = SerializedPropertyUtility.GetManagedObjectForProperty(targetObject, property.propertyPath) as Cluster;
+                    }
+                    else {
+                        ClusterPrefab clusterPrefab = prefabProp.objectReferenceValue as ClusterPrefab;
+                        cluster = new(clusterPrefab);
+                        object parent = SerializedPropertyUtility.GetParentObjectAndMember(targetObject, property.propertyPath, out var memberInfo, out int outIndex);
+                        if (parent != null && memberInfo is FieldInfo fieldInfo) {
+                            fieldInfo.SetValue(parent, cluster);
+                            EditorUtility.SetDirty(targetObject);
+                        }
+                        clusterView.initialized = true;
+                    }
 
                     // key per field instance
                     string key = property.propertyPath + "_" + property.serializedObject.targetObject.GetInstanceID();//GetEntityId();
-                    if (!s_foldouts.TryGetValue(key, out bool isOpen))
-                        isOpen = true;
+                    // if (!s_foldouts.TryGetValue(key, out bool isOpen))
+                    //     isOpen = true;
 
                     // foldout header rect
                     Rect headerRect = new(fieldRect.x, fieldRect.yMax + 4f, fieldRect.width, EditorGUIUtility.singleLineHeight);
-                    isOpen = EditorGUI.Foldout(headerRect, isOpen, "Graph", true);
-                    s_foldouts[key] = isOpen;
+                    clusterView.isOpen = EditorGUI.Foldout(headerRect, clusterView.isOpen, "Graph", true);
 
-                    if (isOpen) {
+                    if (clusterView.isOpen) {
                         // content rect below header
                         Rect drawRect = new(fieldRect.x, headerRect.yMax + 2f, fieldRect.width, 450f);
 
-                        Cluster_Drawer.clusterView = ClusterView.GetClusterView(property);
+                        Cluster_Drawer.clusterView = clusterView;
                         ClusterView.Render(drawRect, cluster, property);
                         //Debug.Log(prefab.cluster.defaultOutput.outputMagnitude);
                     }
@@ -105,6 +137,9 @@ namespace NanoBrain.Unity {
         }
 
         private static void OnSceneGUI(SceneView sceneView) {
+            if (selectedTarget == null)
+                return;
+
             GameObject gameObject = null;
             if (selectedTarget is Component c)
                 gameObject = c.gameObject;
@@ -125,7 +160,12 @@ namespace NanoBrain.Unity {
                     Handles.DrawLine(gameObject.transform.position, gameObject.transform.position + worldVector);
                 }
             }
+        }
 
+        private static void OnSelectionChanged() {
+            foreach (ClusterView clusterView in clusterViews.Values) {
+                clusterView.initialized = false;
+            }
         }
     }
 
diff --git a/Runtime/Scripts/Core/Cluster.cs b/Runtime/Scripts/Core/Cluster.cs
index 78f6504..9417ff1 100644
--- a/Runtime/Scripts/Core/Cluster.cs
+++ b/Runtime/Scripts/Core/Cluster.cs
@@ -176,7 +176,7 @@ namespace NanoBrain {
                     };
                     for (int instanceIx = 1; instanceIx < clonedCluster.instanceCount; instanceIx++) {
                         // Create another sibling
-                        Debug.Log($"create {clonedCluster.prefab.name} sibling");
+                        // Debug.Log($"create {clonedCluster.prefab.name} sibling");
                         Cluster sibling = new(clonedCluster.prefab, this) {
                             name = $"{clonedCluster.baseName}: {instanceIx}",
                             parent = this.parent,
@@ -241,7 +241,7 @@ namespace NanoBrain {
                     }
 
                     clonedNeuron.AddReceiver(receiver, weight);
-                    Debug.Log($"external: {receiver.name} receives from {clonedNeuron.name} {clonedNeuron.GetHashCode()}");
+                    // Debug.Log($"external: {receiver.name} receives from {clonedNeuron.name} {clonedNeuron.GetHashCode()}");
                 }
             }