Trap rooms are entire rooms that act as a large trap for those contained within them. These rooms will lock themselves when triggered (often by pressure plate when stepped on or when an object is removed). Once triggered trap rooms may flood, fill with poison, collapse, have their floors fall away to an abyss, or the walls may slowly move inwards, crushing anyone still in the room. Trap rooms may also be puzzle rooms that become traps if the puzzle is incorrectly solved.

When designing trap rooms consider how they are triggered and how a person or group of people may escape once ensnared. Escape may mean moving into the vents or other area.

There may be skeletal remains in the room.