diff --git a/core/src/main/java/com/volmit/iris/util/mantle/Mantle.java b/core/src/main/java/com/volmit/iris/util/mantle/Mantle.java
index 39665fa10..7457b9f1c 100644
--- a/core/src/main/java/com/volmit/iris/util/mantle/Mantle.java
+++ b/core/src/main/java/com/volmit/iris/util/mantle/Mantle.java
@@ -26,6 +26,7 @@ import com.volmit.iris.engine.data.cache.Cache;
 import com.volmit.iris.engine.framework.Engine;
 import com.volmit.iris.engine.mantle.EngineMantle;
 import com.volmit.iris.engine.mantle.MantleWriter;
+import com.volmit.iris.util.collection.KList;
 import com.volmit.iris.util.collection.KMap;
 import com.volmit.iris.util.documentation.BlockCoordinates;
 import com.volmit.iris.util.documentation.ChunkCoordinates;
@@ -397,7 +398,7 @@ public class Mantle {
     private final AtomicLong oldestTectonicPlate = new AtomicLong(0);
     private final ReentrantLock unloadLock = new ReentrantLock();
     @Getter
-    private final Set<Long> toUnload = new HashSet<>();
+    private final KList<Long> toUnload = new KList<>();
 
     /**
      * Save & unload regions that have not been used for more than the
@@ -420,7 +421,7 @@ public class Mantle {
         }
 
         ioTrim.set(true);
-        unloadLock.lock();
+        //unloadLock.lock();
         try {
             Iris.debug("Trimming Tectonic Plates older than " + Form.duration(adjustedIdleDuration.get(), 0));
             if (lastUse != null) {
@@ -442,14 +443,16 @@ public class Mantle {
         }
     }
 
-    public int unloadTectonicPlate(int tectonicLimit) {
+    public synchronized int unloadTectonicPlate(int tectonicLimit) {
         // todo: Make it advanced with bursts etc
         AtomicInteger i = new AtomicInteger();
         unloadLock.lock();
+        BurstExecutor burst = null;
         try {
-            BurstExecutor burst = MultiBurst.burst.burst(toUnload.size());
-            burst.setMulticore(toUnload.size() > tectonicLimit);
-            for (long id : new ArrayList<>(toUnload)) {
+            KList<Long> copy = toUnload.copy();
+            burst = MultiBurst.burst.burst(copy.size());
+            burst.setMulticore(copy.size() > tectonicLimit);
+            for (long id : copy) {
                 burst.queue(() ->
                         hyperLock.withLong(id, () -> {
                             TectonicPlate m = loadedRegions.get(id);
@@ -469,8 +472,10 @@ public class Mantle {
             }
 
             burst.complete();
-        } catch (Exception e) {
+        } catch (Throwable e) {
             e.printStackTrace();
+            if (burst != null)
+                burst.complete();
         } finally {
             unloadLock.unlock();
             ioTectonicUnload.set(true);