This is a brilliant game! However, I found a bad animation bug. When the XP meter fills, it starts animating. However, xpAnimation[] is getting absolutely flooded. I think there is logic to prevent elements from being added if they're are already in xpAnimation[] but it is not working. Every update another N elements get added, where N equals the size of the XP bar. In moments there are thousands of elements in it. This consumes a ton of CPU time. Once the player levels up, xpAnimation[] is cleared and everything runs smoothly again.