Alright
The game was mediocre, ok to play. It's basically a very basic version of the one popular zombie game where you defend yourself and whatnot (I forget the name >_<).
One of the things however that bothers me is you can only kill an enemy by shooting them directly (by clicking on them). You cant shoot in the direction of their head or wherever you're aiming. You have to directly click the enemy. That should be fixed so you can just aim at the enemy instead of clicking on them.
The graphics are OK, but could use some work. They're very simple and not to original. I don't really have any tips for that though since I'm not an artist :p
So some things to add would be:
+ More weapons
+ More effects/graphics (better)
+ Faster game (meaning it doesn't take as long for the game to get really hard)
Although the funny music was .. funny while killing zombies :)