This was a kind of game design one-liner- a second person shooter. Instead of “I shoot”, “You shoot”- the player selects a character that then shoots them. In the application, you select a character from a typical character-selection screen. That character then shoots you, the screen goes red, and the application starts over.
If you’d like to try it, you can download it here. Note that it’s all 2d (though implemented with OpenGL) and uses Quake3 characters.