Working some one the MCore event classes. I will lie and say that all events are cancellable. In situations where we dont want them to be cancellable we can simply not care about that boolean.

src/com/massivecraft/mcore/event/MCoreAfterPlayerRespawnEvent.java

@@ -12,6 +12,7 @@ public class MCoreAfterPlayerRespawnEvent extends Event implements Runnable
 	// -------------------------------------------- //
 	// REQUIRED EVENT CODE
 	// -------------------------------------------- //
+	
 	private static final HandlerList handlers = new HandlerList();
 	@Override public HandlerList getHandlers() { return handlers; }
 	public static HandlerList getHandlerList() { return handlers; }

src/com/massivecraft/mcore/event/MCoreAfterPlayerTeleportEvent.java

@@ -14,6 +14,7 @@ public class MCoreAfterPlayerTeleportEvent extends Event implements Runnable
 	// -------------------------------------------- //
 	// REQUIRED EVENT CODE
 	// -------------------------------------------- //
+	
 	private static final HandlerList handlers = new HandlerList();
 	@Override public HandlerList getHandlers() { return handlers; }
 	public static HandlerList getHandlerList() { return handlers; }

src/com/massivecraft/mcore/event/MCoreCancellableEvent.java

@@ -1,15 +0,0 @@
-package com.massivecraft.mcore.event;
-
-import org.bukkit.event.Cancellable;
-
-public abstract class MCoreCancellableEvent extends MCoreEvent implements Cancellable
-{
-	// -------------------------------------------- //
-	// FIELDS
-	// -------------------------------------------- //
-	
-	private boolean cancelled = false;
-	@Override public boolean isCancelled() { return this.cancelled; }
-	@Override public void setCancelled(boolean cancelled) { this.cancelled = cancelled; }
-	
-}

src/com/massivecraft/mcore/event/MCoreEvent.java

@@ -1,12 +1,27 @@
 package com.massivecraft.mcore.event;
 
+import java.util.LinkedHashMap;
+import java.util.Map;
+
 import org.bukkit.Bukkit;
+import org.bukkit.event.Cancellable;
 import org.bukkit.event.Event;
 
-public abstract class MCoreEvent extends Event implements Runnable
+public abstract class MCoreEvent extends Event implements Runnable, Cancellable
 {
 	// -------------------------------------------- //
-	// RUN
+	// FIELDS
+	// -------------------------------------------- //
+	
+	private final Map<String, Object> customData = new LinkedHashMap<String, Object>();
+	public Map<String, Object> getCustomData() { return this.customData; }
+	
+	private boolean cancelled = false;
+	@Override public boolean isCancelled() { return this.cancelled; }
+	@Override public void setCancelled(boolean cancelled) { this.cancelled = cancelled; }
+	
+	// -------------------------------------------- //
+	// OVERRIDE: RUNNABLE
 	// -------------------------------------------- //
 	
 	@Override

src/com/massivecraft/mcore/event/MCorePlayerLeaveEvent.java

@@ -23,6 +23,7 @@ public class MCorePlayerLeaveEvent extends Event implements Runnable
 	// -------------------------------------------- //
 	// REQUIRED EVENT CODE
 	// -------------------------------------------- //
+	
 	private static final HandlerList handlers = new HandlerList();
 	@Override public HandlerList getHandlers() { return handlers; }
 	public static HandlerList getHandlerList() { return handlers; }