This wasn't that bad of a game. I admit that it's not really that interesting. I don't see what the logic is in pointing out different zombies. You want to kill them all! At least the designs were pretty good. Zombies really have given us some good designs like that.
Maybe that's one reason why they're so popular. The music was nice. You probably could make them a little more well drawn. I didn't know you had to go to the other side of the picture in some levels. Not great, but far from bad.