Falling Room Trap

This 10-foot-square room has metal walls, ceiling, and floors. The only exit is a hatch in the ceiling. A wooden board lies on the floor.

The room is a malfunctioning elevator. When the room’s door closes while the room contains more than 50 pounds of weight, the room plunges 30 feet down its elevator shaft before coming to a sudden halt. Each creature in the elevator takes 10 (3d6) bludgeoning damage from the fall. The room’s door now leads to a lower dungeon level or (if no lower level exists) a small room containing a treasure hoard or a Minor Treasure. Opening the ceiling hatch allows a creature to climb the elevator shaft and return to the original floor.

While the room occupies the lower level, re-closing the door while the room contains at least 50 pounds of weight causes the elevator to rocket 30 feet back to its original position. Upon arrival, each creature in the elevator is catapulted against the ceiling, taking 10 (3d6) bludgeoning damage.

Board. The wooden board is a sign reading “Out of Order,” lying upside down.

Door. The door opens inward into the elevator room. An Engineering or Investigation check, or an examination of the door, reveals that the door connects to a mechanism that triggers when the door closes.

Room. A Perception check, or jumping up and down inside the room, reveals that the room trembles when creatures move about inside, as if it weren’t fixed in place.

Hatch. The hatch on the ceiling is metal. It’s locked, and also warped and damaged as if it had been struck.