Player one, you are the craft with a flame figure on the back. Player two, you are the craft that says "me" on the back. Player one, left arrow key to rotate left and right arrow key to rotate right. Player two, A to rotate left and D to rotate right. Player one, 0 to shoot. Player two, spacebar to shoot. Both players, don't touch the star. Score as many hits son the opponent as possible.
This game is based off the very first video game, Spacewar! (yes, it predates Pong), so credits are pretty much to Steve Russel, Martin Graetz, and Wayne Wiitanen, the hackers who made the game way back in 1962.