As I mentioned earlier, I am no artist. But I've grown rather fond of the circles and squares in my game. In the last picture you can see all the major players: (from left to right) Ammo Drop (Light Brown), Wolf Zombie (Brown), Fat Zombie (Large, Gray), Green Zombie (self-explanatory), The Player (Blue), and a Normal Zombie (Small, Gray). The black squares are obstacles that are generated randomly on each play-through, and the light blue area is the player's attack range.
I've had a lot of fun doing this game jam and I look forward both to playing everyone's game and to continuing to add content to my own game. Good luck!