You can't help but hear "Waluigi Pinball" in your head. Party Hard!
The original pilot episode for Invader Zim, completed in 1999, was never aired until 2011. This episode was also created as an animation test so Invader Zim could be publised. Billy West was the original voice of Zim, but only for this episode. Because Billy West sounds too much like Fry in Futurama, he was replaced with Richard Steven Horvitz. Enjoy, Invaders.