Very Nice!
I played this game for many hours of my life, and it hasn't yet gotten old. I love how you made all of the attackers different on each level, the were football zombies slow, while the pac-ghosts were fast. I also lked the choice between turret defence and on-foot defence, and the choice of protecting something. All in all a great submission and I hope to see more from you.
Thanks,
Vince
(P.S. Hehe, nazi bowlers)