diff --git a/build.gradle b/build.gradle
index 198e19a0..6503c89e 100644
--- a/build.gradle
+++ b/build.gradle
@@ -10,7 +10,7 @@ buildscript {
 }
 
 group = 'com.boydti.fawe'
-version = '3.3.20'
+version = '3.3.21'
 description = """FastAsyncWorldEdit"""
 
 subprojects {
diff --git a/bukkit/build/resources/main/plugin.yml b/bukkit/build/resources/main/plugin.yml
index 0153138e..fc0da240 100644
--- a/bukkit/build/resources/main/plugin.yml
+++ b/bukkit/build/resources/main/plugin.yml
@@ -1,6 +1,6 @@
 name: FastAsyncWorldEdit
 main: com.boydti.fawe.bukkit.FaweBukkit
-version: 3.3.20
+version: 3.3.21
 description: Fast Async WorldEdit plugin
 authors: [Empire92]
 loadbefore: [WorldEdit]
diff --git a/bukkit/src/main/java/com/boydti/fawe/bukkit/v1_8/BukkitQueue_1_8.java b/bukkit/src/main/java/com/boydti/fawe/bukkit/v1_8/BukkitQueue_1_8.java
index aa6a6d0c..a36ab31a 100644
--- a/bukkit/src/main/java/com/boydti/fawe/bukkit/v1_8/BukkitQueue_1_8.java
+++ b/bukkit/src/main/java/com/boydti/fawe/bukkit/v1_8/BukkitQueue_1_8.java
@@ -423,7 +423,9 @@ public class BukkitQueue_1_8 extends BukkitQueue_All {
             }, 1);
             return true;
         } catch (final Exception e) {
-            e.printStackTrace();
+            if (Thread.currentThread() == Fawe.get().getMainThread()) {
+                e.printStackTrace();
+            }
         }
         return false;
     }
diff --git a/bukkit/src/main/java/com/boydti/fawe/bukkit/v1_9/BukkitQueue_1_9.java b/bukkit/src/main/java/com/boydti/fawe/bukkit/v1_9/BukkitQueue_1_9.java
index a8efeee5..4ab80c10 100644
--- a/bukkit/src/main/java/com/boydti/fawe/bukkit/v1_9/BukkitQueue_1_9.java
+++ b/bukkit/src/main/java/com/boydti/fawe/bukkit/v1_9/BukkitQueue_1_9.java
@@ -212,7 +212,9 @@ public class BukkitQueue_1_9 extends BukkitQueue_All {
             }
             return true;
         } catch (final Throwable e) {
-            e.printStackTrace();
+            if (Thread.currentThread() == Fawe.get().getMainThread()) {
+                e.printStackTrace();
+            }
         }
         return false;
     }
diff --git a/bukkit/src/main/java/com/boydti/fawe/bukkit/v1_9/BukkitQueue_1_9_R1.java b/bukkit/src/main/java/com/boydti/fawe/bukkit/v1_9/BukkitQueue_1_9_R1.java
index ac095223..ad7364a8 100644
--- a/bukkit/src/main/java/com/boydti/fawe/bukkit/v1_9/BukkitQueue_1_9_R1.java
+++ b/bukkit/src/main/java/com/boydti/fawe/bukkit/v1_9/BukkitQueue_1_9_R1.java
@@ -185,7 +185,9 @@ public class BukkitQueue_1_9_R1 extends BukkitQueue_All {
             }
             return true;
         } catch (final Throwable e) {
-            e.printStackTrace();
+            if (Thread.currentThread() == Fawe.get().getMainThread()) {
+                e.printStackTrace();
+            }
         }
         return false;
     }
diff --git a/bukkit/src/main/resources/plugin.yml b/bukkit/src/main/resources/plugin.yml
index 0153138e..fc0da240 100644
--- a/bukkit/src/main/resources/plugin.yml
+++ b/bukkit/src/main/resources/plugin.yml
@@ -1,6 +1,6 @@
 name: FastAsyncWorldEdit
 main: com.boydti.fawe.bukkit.FaweBukkit
-version: 3.3.20
+version: 3.3.21
 description: Fast Async WorldEdit plugin
 authors: [Empire92]
 loadbefore: [WorldEdit]
diff --git a/core/src/main/java/com/boydti/fawe/util/TaskManager.java b/core/src/main/java/com/boydti/fawe/util/TaskManager.java
index c94c589b..d0f38af6 100644
--- a/core/src/main/java/com/boydti/fawe/util/TaskManager.java
+++ b/core/src/main/java/com/boydti/fawe/util/TaskManager.java
@@ -56,4 +56,38 @@ public abstract class TaskManager {
             }
         });
     }
+
+    public <T> T sync(final RunnableVal<T> function) {
+        if (Fawe.get().getMainThread() == Thread.currentThread()) {
+            function.run();
+            return function.value;
+        }
+        RunnableVal<RuntimeException> run = new RunnableVal<RuntimeException>() {
+            @Override
+            public void run(RuntimeException value) {
+                try {
+                    function.run();
+                } catch (RuntimeException e) {
+                    this.value = e;
+                } catch (Throwable neverHappens) {
+                    neverHappens.printStackTrace();
+                }
+                synchronized (function) {
+                    function.notifyAll();
+                }
+            }
+        };
+        TaskManager.IMP.task(run);
+        if (run.value != null) {
+            throw run.value;
+        }
+        try {
+            synchronized (function) {
+                function.wait(15000);
+            }
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+        return function.value;
+    }
 }
diff --git a/core/src/main/java/com/boydti/fawe/wrappers/WorldWrapper.java b/core/src/main/java/com/boydti/fawe/wrappers/WorldWrapper.java
index 329c4b14..ea0dec4a 100644
--- a/core/src/main/java/com/boydti/fawe/wrappers/WorldWrapper.java
+++ b/core/src/main/java/com/boydti/fawe/wrappers/WorldWrapper.java
@@ -90,28 +90,73 @@ public class WorldWrapper extends AbstractWorld {
     }
 
     @Override
-    public boolean generateTree(EditSession editSession, Vector pt) throws MaxChangedBlocksException {
-        return parent.generateTree(editSession, pt);
+    public boolean generateTree(final EditSession editSession, final Vector pt) throws MaxChangedBlocksException {
+        return TaskManager.IMP.sync(new RunnableVal<Boolean>() {
+            @Override
+            public void run(Boolean ignore) {
+                try {
+                    this.value = parent.generateTree(editSession, pt);
+                } catch (MaxChangedBlocksException e) {
+                    e.printStackTrace();
+                }
+            }
+        });
     }
 
     @Override
-    public boolean generateBigTree(EditSession editSession, Vector pt) throws MaxChangedBlocksException {
-        return parent.generateBigTree(editSession, pt);
+    public boolean generateBigTree(final EditSession editSession, final Vector pt) throws MaxChangedBlocksException {
+        return TaskManager.IMP.sync(new RunnableVal<Boolean>() {
+            @Override
+            public void run(Boolean ignore) {
+                try {
+                    this.value = parent.generateBigTree(editSession, pt);
+                } catch (MaxChangedBlocksException e) {
+                    e.printStackTrace();
+                }
+            }
+        });
     }
 
     @Override
-    public boolean generateBirchTree(EditSession editSession, Vector pt) throws MaxChangedBlocksException {
-        return parent.generateBirchTree(editSession, pt);
+    public boolean generateBirchTree(final EditSession editSession, final Vector pt) throws MaxChangedBlocksException {
+        return TaskManager.IMP.sync(new RunnableVal<Boolean>() {
+            @Override
+            public void run(Boolean ignore) {
+                try {
+                    this.value = parent.generateBirchTree(editSession, pt);
+                } catch (MaxChangedBlocksException e) {
+                    e.printStackTrace();
+                }
+            }
+        });
     }
 
     @Override
-    public boolean generateRedwoodTree(EditSession editSession, Vector pt) throws MaxChangedBlocksException {
-        return parent.generateRedwoodTree(editSession, pt);
+    public boolean generateRedwoodTree(final EditSession editSession, final Vector pt) throws MaxChangedBlocksException {
+        return TaskManager.IMP.sync(new RunnableVal<Boolean>() {
+            @Override
+            public void run(Boolean ignore) {
+                try {
+                    this.value = parent.generateRedwoodTree(editSession, pt);
+                } catch (MaxChangedBlocksException e) {
+                    e.printStackTrace();
+                }
+            }
+        });
     }
 
     @Override
-    public boolean generateTallRedwoodTree(EditSession editSession, Vector pt) throws MaxChangedBlocksException {
-        return parent.generateTallRedwoodTree(editSession, pt);
+    public boolean generateTallRedwoodTree(final EditSession editSession, final Vector pt) throws MaxChangedBlocksException {
+        return TaskManager.IMP.sync(new RunnableVal<Boolean>() {
+            @Override
+            public void run(Boolean ignore) {
+                try {
+                    this.value = parent.generateTallRedwoodTree(editSession, pt);
+                } catch (MaxChangedBlocksException e) {
+                    e.printStackTrace();
+                }
+            }
+        });
     }
 
     @Override
@@ -293,8 +338,17 @@ public class WorldWrapper extends AbstractWorld {
     }
 
     @Override
-    public boolean generateTree(TreeGenerator.TreeType type, EditSession editSession, Vector position) throws MaxChangedBlocksException {
-        return parent.generateTree(type, editSession, position);
+    public boolean generateTree(final TreeGenerator.TreeType type, final EditSession editSession, final Vector position) throws MaxChangedBlocksException {
+        return TaskManager.IMP.sync(new RunnableVal<Boolean>() {
+            @Override
+            public void run(Boolean ignore) {
+                try {
+                    this.value = parent.generateTree(editSession, position);
+                } catch (MaxChangedBlocksException e) {
+                    e.printStackTrace();
+                }
+            }
+        });
     }
 
     @Override
diff --git a/forge/src/main/java/com/boydti/fawe/forge/SpongeMain.java b/forge/src/main/java/com/boydti/fawe/forge/SpongeMain.java
index 81521f77..a6634366 100644
--- a/forge/src/main/java/com/boydti/fawe/forge/SpongeMain.java
+++ b/forge/src/main/java/com/boydti/fawe/forge/SpongeMain.java
@@ -18,7 +18,7 @@ import org.spongepowered.api.plugin.PluginContainer;
 import org.spongepowered.api.profile.GameProfileManager;
 import org.spongepowered.api.world.World;
 
-@Plugin(id = "com.boydti.fawe", name = "FastAsyncWorldEdit", description = "Lagless WorldEdit, Area restrictions, Memory mangement, Block logging", url = "https://github.com/boy0001/FastAsyncWorldedit", version = "3.3.20")
+@Plugin(id = "com.boydti.fawe", name = "FastAsyncWorldEdit", description = "Lagless WorldEdit, Area restrictions, Memory mangement, Block logging", url = "https://github.com/boy0001/FastAsyncWorldedit", version = "3.3.21")
 public class SpongeMain {
     public PluginContainer plugin;
 
diff --git a/pom.xml b/pom.xml
index 8610c1b1..fa993689 100644
--- a/pom.xml
+++ b/pom.xml
@@ -8,7 +8,7 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
     <artifactId>FastAsyncWorldEdit</artifactId>
-    <version>3.3.20</version>
+    <version>3.3.21</version>
     <name>FastAsyncWorldEdit</name>
     <packaging>jar</packaging>
     <build>