It's a fun game. I like that I was thinking "hey, this game is super easy", until I had like 50 zombies and a lot of dudes shooting and I went back to 10 lol. Just careful with the audio, it becomes a real loud clusterfuck after 30-40 zombies. If I can give another piece of advice, make the game "pausable" with ESC too, because the way it is right now your zombies will go to the upper right corner until you hit the pause button (nice pause animation btw).