diff --git a/src/com/massivecraft/massivecore/collections/MassiveSet.java b/src/com/massivecraft/massivecore/collections/MassiveSet.java
index 5fa3341e..b0124dba 100644
--- a/src/com/massivecraft/massivecore/collections/MassiveSet.java
+++ b/src/com/massivecraft/massivecore/collections/MassiveSet.java
@@ -3,7 +3,9 @@ package com.massivecraft.massivecore.collections;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.HashSet;
 import java.util.LinkedHashSet;
+import java.util.List;
 
 /**
  * This subclass adds better constructors. 
@@ -51,5 +53,24 @@ public class MassiveSet<E> extends LinkedHashSet<E>
 	{
 		this(Arrays.asList(elements));
 	}
+	
+	// -------------------------------------------- //
+	// OPTIMIZE: REMOVE ALL & RETAIN ALL
+	// -------------------------------------------- //
+	// This will greatly reduce the complexity in cases with big sizes.
+	
+	@Override
+	public boolean removeAll(Collection<?> c)
+	{
+		if (c instanceof List) c = new HashSet<Object>(c);
+		return super.removeAll(c);
+	}
+	
+	@Override
+	public boolean retainAll(Collection<?> c)
+	{
+		if (c instanceof List) c = new HashSet<Object>(c);
+		return super.retainAll(c);
+	}
 
 }
diff --git a/src/com/massivecraft/massivecore/event/EventMassiveCore.java b/src/com/massivecraft/massivecore/event/EventMassiveCore.java
index 7bd8a4be..f9e75bcd 100644
--- a/src/com/massivecraft/massivecore/event/EventMassiveCore.java
+++ b/src/com/massivecraft/massivecore/event/EventMassiveCore.java
@@ -44,4 +44,13 @@ public abstract class EventMassiveCore extends Event implements Runnable, Cancel
 		super(isAsync);
 	}
 	
+	// -------------------------------------------- //
+	// UTIL
+	// -------------------------------------------- //
+	
+	public boolean isSynchronous()
+	{
+		return !this.isAsynchronous();
+	}
+	
 }