Player 1 (left) uses WASD and Player 2 (right) uses the arrow keys. The aim of the game is to try to cover the screen with your colour before 30 seconds is up. The player with the most ground wins. Watch out for the white squares, they'll take away your progress. The players can change their colour when the settings button is clicked, but not during the game - P1 = 1 key, P2 = 2 key.
@FontGod for the Minecraft font. Sorry, it's a little glitchy, and I don't know how to determine who won.