Minecraft wiki entry for Trap_design, associated text: The owner of a large underground mansion is being chased by another player. The owner escapes through an iron door controlled by a pressure plate. On the other side, they hit a button. The pursuer sees him open the door by the pressure plate and follows him, but the door doesn't open. Instead, a series of pistons opens a hole and pushes the assailant into it. Once the pistons extinguish the light from the opening, it is pitch black.