This is a small project we did during GlobalGameJam 2010 in 48 hours.
It's a simple player arcade game, where the player has to survive as long as possible. To do so, you have to shoot keys at the enemies, which will open them up, and delete them.
Howver, the world concists of 3 colors, and both the environment, and the enemies share them. this makes it impossible at times to find enemies. The player has an alternative fire, to shoot ink bullets
who spat on the floor, leaving a background color, which reveals the enemies.
I have included the source code, but be warned, it's horrible; after 40 hours of no sleep and time pressure, some nasty stuff was used (This does not, in any way, represent my current programming skills)