diff --git a/QSB/Animation/NPC/Patches/SolanumPatches.cs b/QSB/Animation/NPC/Patches/SolanumPatches.cs
index 0fbe03b6..69c3e616 100644
--- a/QSB/Animation/NPC/Patches/SolanumPatches.cs
+++ b/QSB/Animation/NPC/Patches/SolanumPatches.cs
@@ -17,6 +17,11 @@ public class SolanumPatches : QSBPatch
 	[HarmonyPatch(typeof(SolanumAnimController), nameof(SolanumAnimController.LateUpdate))]
 	public static bool SolanumLateUpdateReplacement(SolanumAnimController __instance)
 	{
+		if (!QSBWorldSync.AllObjectsReady)
+		{
+			return true;
+		}
+
 		if (__instance._animatorStateEvents == null)
 		{
 			__instance._animatorStateEvents = __instance._animator.GetBehaviour<AnimatorStateEvents>();
@@ -43,6 +48,10 @@ public class SolanumPatches : QSBPatch
 	[HarmonyPatch(typeof(NomaiConversationManager), nameof(NomaiConversationManager.Update))]
 	public static bool ReplacementUpdate(NomaiConversationManager __instance)
 	{
+		if (!QSBWorldSync.AllObjectsReady)
+		{
+			return true;
+		}
 		var qsbObj = __instance._solanumAnimController.GetWorldObject<QSBSolanumAnimController>();
 		__instance._playerInWatchVolume = qsbObj.Trigger.Occupants.Any();
 
@@ -206,4 +215,4 @@ public class SolanumPatches : QSBPatch
 
 		return false;
 	}
-}
\ No newline at end of file
+}
diff --git a/QSB/EchoesOfTheEye/QSBRotatingElements.cs b/QSB/EchoesOfTheEye/QSBRotatingElements.cs
index 05b08c69..9be7c3eb 100644
--- a/QSB/EchoesOfTheEye/QSBRotatingElements.cs
+++ b/QSB/EchoesOfTheEye/QSBRotatingElements.cs
@@ -37,10 +37,13 @@ internal abstract class QSBRotatingElements<T, U> : LinkedWorldObject<T, U>
 	{
 		base.OnRemoval();
 
-		foreach (var lightSensor in _qsbLightSensors)
+		if (_qsbLightSensors != null)
 		{
-			lightSensor.OnDetectLocalLight -= OnDetectLocalLight;
-			lightSensor.OnDetectLocalDarkness -= OnDetectLocalDarkness;
+			foreach (var lightSensor in _qsbLightSensors)
+			{
+				lightSensor.OnDetectLocalLight -= OnDetectLocalLight;
+				lightSensor.OnDetectLocalDarkness -= OnDetectLocalDarkness;
+			}
 		}
 	}
 
diff --git a/QSB/ItemSync/WorldObjects/Items/QSBItem.cs b/QSB/ItemSync/WorldObjects/Items/QSBItem.cs
index bfb67695..c1417b32 100644
--- a/QSB/ItemSync/WorldObjects/Items/QSBItem.cs
+++ b/QSB/ItemSync/WorldObjects/Items/QSBItem.cs
@@ -1,9 +1,11 @@
 using Cysharp.Threading.Tasks;
+using OWML.Common;
 using QSB.ItemSync.Messages;
 using QSB.ItemSync.WorldObjects.Sockets;
 using QSB.Messaging;
 using QSB.Player;
 using QSB.SectorSync.WorldObjects;
+using QSB.Utility;
 using QSB.WorldSync;
 using System.Threading;
 using UnityEngine;
diff --git a/QSB/MeteorSync/MeteorManager.cs b/QSB/MeteorSync/MeteorManager.cs
index 65226a38..29c841f8 100644
--- a/QSB/MeteorSync/MeteorManager.cs
+++ b/QSB/MeteorSync/MeteorManager.cs
@@ -17,7 +17,9 @@ public class MeteorManager : WorldObjectManager
 		// wait for all late initializers (which includes meteor launchers) to finish
 		await UniTask.WaitUntil(() => LateInitializerManager.isDoneInitializing, cancellationToken: ct);
 
-		WhiteHoleVolume = QSBWorldSync.GetUnityObject<WhiteHoleVolume>();
+		// NH can make multiple so ensure its the stock whitehole 
+		var whiteHole = QSBWorldSync.GetUnityObjects<AstroObject>().First(x => x.GetAstroObjectName() == AstroObject.Name.WhiteHole);
+		WhiteHoleVolume = whiteHole?.GetComponentInChildren<WhiteHoleVolume>();
 		QSBWorldSync.Init<QSBFragment, FragmentIntegrity>();
 		QSBWorldSync.Init<QSBMeteorLauncher, MeteorLauncher>();
 		QSBWorldSync.Init<QSBMeteor, MeteorController>();
diff --git a/QSB/ModelShip/ModelShipManager.cs b/QSB/ModelShip/ModelShipManager.cs
index 23417fb3..4caae0ff 100644
--- a/QSB/ModelShip/ModelShipManager.cs
+++ b/QSB/ModelShip/ModelShipManager.cs
@@ -37,6 +37,13 @@ internal class ModelShipManager : WorldObjectManager
 
 	public override async UniTask BuildWorldObjects(OWScene scene, CancellationToken ct)
 	{
+		// NH can remove this
+		var modelShip = QSBWorldSync.GetUnityObject<RemoteFlightConsole>()._modelShipBody;
+		if (!modelShip)
+		{
+			return;
+		}
+
 		if (QSBCore.IsHost)
 		{
 			Instantiate(QSBNetworkManager.singleton.ModelShipPrefab).SpawnWithServerAuthority();
diff --git a/QSB/QSBCore.cs b/QSB/QSBCore.cs
index 9cf2191f..48e9137c 100644
--- a/QSB/QSBCore.cs
+++ b/QSB/QSBCore.cs
@@ -69,11 +69,14 @@ public class QSBCore : ModBehaviour
 	public static DebugSettings DebugSettings { get; private set; } = new();
 	public static Storage Storage { get; private set; } = new();
 
+	public const string NEW_HORIZONS = "xen.NewHorizons";
+	public const string NEW_HORIZONS_COMPAT = "xen.NHQSBCompat";
+
 	public static readonly string[] IncompatibleMods =
 	{
 		// incompatible mods
 		"Raicuparta.NomaiVR",
-		"xen.NewHorizons",
+		// "xen.NewHorizons",
 		"Vesper.AutoResume",
 		"Vesper.OuterWildsMMO",
 		"_nebula.StopTime",
@@ -127,6 +130,8 @@ public class QSBCore : ModBehaviour
 		Helper = ModHelper;
 		DebugLog.ToConsole($"* Start of QSB version {QSBVersion} - authored by {Helper.Manifest.Author}", MessageType.Info);
 
+		CheckCompatibilityMods();
+
 		DebugSettings = Helper.Storage.Load<DebugSettings>("debugsettings.json") ?? new DebugSettings();
 		Storage = Helper.Storage.Load<Storage>("storage.json") ?? new Storage();
 
@@ -270,6 +275,26 @@ public class QSBCore : ModBehaviour
 			DebugLog.ToConsole($"DEBUG MODE = {DebugSettings.DebugMode}");
 		}
 	}
+
+	private void CheckCompatibilityMods()
+	{
+		var mainMod = "";
+		var compatMod = "";
+		var missingCompat = false;
+
+		if (Helper.Interaction.ModExists(NEW_HORIZONS) && !Helper.Interaction.ModExists(NEW_HORIZONS_COMPAT))
+		{
+			mainMod = NEW_HORIZONS;
+			compatMod = NEW_HORIZONS_COMPAT;
+			missingCompat = true;
+		}
+
+		if (missingCompat)
+		{
+			DebugLog.ToConsole($"FATAL - You have mod \"{mainMod}\" installed, which is not compatible with QSB without the compatibility mod \"{compatMod}\". " +
+				$"Either disable the mod, or install/enable the compatibility mod.", MessageType.Fatal);
+		}
+	}
 }
 
 /*
diff --git a/QSB/SectorSync/QSBSectorManager.cs b/QSB/SectorSync/QSBSectorManager.cs
index 3d345bfd..389060ff 100644
--- a/QSB/SectorSync/QSBSectorManager.cs
+++ b/QSB/SectorSync/QSBSectorManager.cs
@@ -91,11 +91,15 @@ public class QSBSectorManager : WorldObjectManager
 
 		// time loop spinning ring
 		{
+			// NH can remove this
 			var TimeLoopRing_Body = GameObject.Find("TimeLoopRing_Body");
-			var Sector_TimeLoopInterior = GameObject.Find("Sector_TimeLoopInterior").GetComponent<Sector>();
-			// use the same trigger as the parent sector
-			FakeSector.Create(TimeLoopRing_Body, Sector_TimeLoopInterior,
-				x => x._triggerRoot = Sector_TimeLoopInterior._triggerRoot);
+			if (TimeLoopRing_Body)
+			{
+				var Sector_TimeLoopInterior = GameObject.Find("Sector_TimeLoopInterior").GetComponent<Sector>();
+				// use the same trigger as the parent sector
+				FakeSector.Create(TimeLoopRing_Body, Sector_TimeLoopInterior,
+					x => x._triggerRoot = Sector_TimeLoopInterior._triggerRoot);
+			}
 		}
 
 		// TH elevators
diff --git a/QSB/Syncs/Occasional/OccasionalManager.cs b/QSB/Syncs/Occasional/OccasionalManager.cs
index 6f229299..c53a6dfd 100644
--- a/QSB/Syncs/Occasional/OccasionalManager.cs
+++ b/QSB/Syncs/Occasional/OccasionalManager.cs
@@ -7,6 +7,7 @@ using System.Threading;
 
 namespace QSB.Syncs.Occasional;
 
+// BUG: somehow, not including DontDestroyOnLoad things makes this fuck up with NH
 internal class OccasionalManager : WorldObjectManager
 {
 	public override WorldObjectScene WorldObjectScene => WorldObjectScene.SolarSystem;
@@ -21,6 +22,11 @@ internal class OccasionalManager : WorldObjectManager
 
 		foreach (var proxy in cannon._realDebrisSectorProxies)
 		{
+			// NH can remove these
+			if (!proxy)
+			{
+				continue;
+			}
 			SpawnOccasional(proxy.transform.root.GetAttachedOWRigidbody(), gdBody);
 		}
 
@@ -58,4 +64,4 @@ internal class OccasionalManager : WorldObjectManager
 
 		Bodies.Clear();
 	}
-}
\ No newline at end of file
+}
diff --git a/QSB/WorldSync/QSBWorldSync.cs b/QSB/WorldSync/QSBWorldSync.cs
index c57d6eeb..d6446f37 100644
--- a/QSB/WorldSync/QSBWorldSync.cs
+++ b/QSB/WorldSync/QSBWorldSync.cs
@@ -11,6 +11,7 @@ using QSB.Utility;
 using QSB.Utility.LinkedWorldObject;
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Linq;
 using System.Threading;
 using UnityEngine;
@@ -20,7 +21,8 @@ namespace QSB.WorldSync;
 public static class QSBWorldSync
 {
 	public static WorldObjectManager[] Managers;
-	public static string WorldObjectsHash { get; private set; }
+	public static Dictionary<string, string> ManagerHashes { get; private set; } = new();
+	public static Dictionary<string, List<IWorldObject>> ManagerToBuiltObjects { get; private set; } = new();
 
 	/// <summary>
 	/// Set when all WorldObjectManagers have called Init() on all their objects (AKA all the objects are created)
@@ -85,12 +87,20 @@ public static class QSBWorldSync
 
 		DeterministicManager.OnWorldObjectsAdded();
 
-		WorldObjectsHash = WorldObjects.Select(x => x.GetType().Name).GetMD5Hash();
-		DebugLog.DebugWrite($"WorldObject hash is {WorldObjectsHash}");
+		foreach (var item in ManagerToBuiltObjects)
+		{
+			var worldObjects = item.Value;
+			var hash = worldObjects.Select(x => x.GetType().Name).GetMD5Hash();
+			ManagerHashes[item.Key] = hash;
+		}
 
 		if (!QSBCore.IsHost)
 		{
-			new WorldObjectsHashMessage().Send();
+			foreach (var item in ManagerHashes)
+			{
+				new WorldObjectsHashMessage(item.Key, item.Value).Send();
+			}
+
 			new RequestLinksMessage().Send();
 		}
 
@@ -135,6 +145,9 @@ public static class QSBWorldSync
 		AllObjectsAdded = false;
 		AllObjectsReady = false;
 
+		ManagerToBuiltObjects = new();
+		ManagerHashes = new();
+
 		GameReset();
 
 		foreach (var worldObject in WorldObjects)
@@ -193,7 +206,8 @@ public static class QSBWorldSync
 			{
 				// So objects have time to be deleted, made, whatever
 				// i.e. wait until Start has been called
-				Delay.RunNextFrame(() => BuildWorldObjects(loadScene).Forget());
+				// TODO: see if this number of frames actually works. TWEAK!
+				Delay.RunFramesLater(10, () => BuildWorldObjects(loadScene).Forget());
 			}
 		};
 
@@ -306,12 +320,55 @@ public static class QSBWorldSync
 		=> GetUnityObjects<TUnityObject>().Single();
 
 	/// <summary>
-	/// not deterministic across platforms
+	/// not deterministic across platforms.
+	/// excludes prefabs and DontDestroyOnLoad objects.
 	/// </summary>
 	public static IEnumerable<TUnityObject> GetUnityObjects<TUnityObject>()
 		where TUnityObject : MonoBehaviour
 		=> Resources.FindObjectsOfTypeAll<TUnityObject>()
-			.Where(x => x.gameObject.scene.name != null);
+			.Where(x => x.gameObject.scene.name is not (null or "DontDestroyOnLoad"));
+
+	// https://stackoverflow.com/a/48570616
+	public static string NameOfCallingClass()
+	{
+		string fullName;
+		Type declaringType;
+		var skipFrames = 2;
+		do
+		{
+			var method = new StackFrame(skipFrames, false).GetMethod();
+			declaringType = method.DeclaringType;
+			if (declaringType == null)
+			{
+				return method.Name;
+			}
+
+			skipFrames++;
+			fullName = CleanupFullName(declaringType.FullName);
+		}
+		while (declaringType.Module.Name.Equals("mscorlib.dll", StringComparison.OrdinalIgnoreCase) || declaringType == typeof(QSBWorldSync));
+
+		return fullName;
+	}
+
+	private static string CleanupFullName(string fullName)
+	{
+		var ret = fullName;
+
+		var indexOfPlus = fullName.LastIndexOf('+');
+		if (indexOfPlus != -1)
+		{
+			ret = fullName.Remove(indexOfPlus);
+		}
+
+		var indexOfDot = ret.LastIndexOf('.');
+		if (indexOfDot != -1)
+		{
+			ret = ret.Substring(indexOfDot + 1);
+		}
+
+		return ret;
+	}
 
 	public static void Init<TWorldObject, TUnityObject>()
 		where TWorldObject : WorldObject<TUnityObject>, new()
@@ -382,6 +439,17 @@ public static class QSBWorldSync
 			return;
 		}
 
+		var className = NameOfCallingClass();
+
+		if (!ManagerToBuiltObjects.ContainsKey(className))
+		{
+			ManagerToBuiltObjects.Add(className, new List<IWorldObject> { worldObject });
+		}
+		else
+		{
+			ManagerToBuiltObjects[className].Add(worldObject);
+		}
+
 		WorldObjects.Add(worldObject);
 		RequestInitialStatesMessage.SendInitialState += worldObject.SendInitialState;
 
diff --git a/QSB/WorldSync/WorldObjectsHashMessage.cs b/QSB/WorldSync/WorldObjectsHashMessage.cs
index 4d5e6bd2..fc18ec15 100644
--- a/QSB/WorldSync/WorldObjectsHashMessage.cs
+++ b/QSB/WorldSync/WorldObjectsHashMessage.cs
@@ -8,23 +8,19 @@ namespace QSB.WorldSync;
 /// <summary>
 /// sends QSBWorldSync.WorldObjectsHash to the server for sanity checking
 /// </summary>
-internal class WorldObjectsHashMessage : QSBMessage<string>
+internal class WorldObjectsHashMessage : QSBMessage<(string managerName, string hash)>
 {
-	public WorldObjectsHashMessage() : base(QSBWorldSync.WorldObjectsHash) => To = 0;
+	public WorldObjectsHashMessage(string managerName, string hash) : base((managerName, hash)) => To = 0;
 
 	public override void OnReceiveRemote()
 	{
-		var serverHash = QSBWorldSync.WorldObjectsHash;
+		var serverHash = QSBWorldSync.ManagerHashes[Data.managerName];
 
-		if (serverHash != Data)
+		if (serverHash != Data.hash)
 		{
 			// oh fuck oh no oh god
-			DebugLog.ToConsole($"Kicking {From} because their WorldObjects hash is wrong. (server:{serverHash}, client:{Data})", MessageType.Error);
-			new PlayerKickMessage(From, $"WorldObject hash error. (Server:{serverHash}, Client:{Data})").Send();
-		}
-		else
-		{
-			DebugLog.DebugWrite($"WorldObject hash from {From} verified!", MessageType.Success);
+			DebugLog.ToConsole($"Kicking {From} because their WorldObjects hash for {Data.managerName} is wrong. (server:{serverHash}, client:{Data.hash})", MessageType.Error);
+			new PlayerKickMessage(From, $"WorldObject hash error for {Data.managerName}. (Server:{serverHash}, Client:{Data.hash})").Send();
 		}
 	}
 }