Doom 2 Easter Egg

Historia

Shoot the final boss–a giant demon head–with a rocket launcher, then enter the “noclip” cheat code. Walk through the hole you’ve made in the boss’s head, and into a room. In the room you’ll find another head, that of John Romero, the creator of the Doom series. He’ll say, backwards, “To win the game, you must kill me, John Romero.” Shoot him a bunch of times and you indeed win the game.