Burning Box (5e Trap)
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Mechanical Input, Magical Output
The Burning Box is a system of pressure plates, pipes, and nozzles that floods a room with flammable gas, and then erupts into flames when tripped. A successful DC(15) Investigation check can reveal a series of nozzles embedded all over the wall, and a DC(14) Perception check can be used to smell the gas lingering within the chamber.
The chamber can be successfully disarmed by thoroughly plugging up every nozzle in the room, which requires a DC(14) Investigation check to locate them all and properly disable them. An array of very delicate pressure plates rests on the floor, but trying to disarm the trap this way requires a DC(18) Sleight of Hand check to avoid igniting the room.
To safely traverse the room, a creature must succeed on a DC(14) Perception check to identify a safe path through the pressure plates on the floor, and then a DC(10) Acrobatics check to avoid accidentally stepping on a pressure plate. If the room ignites, all creatures within take 3d12 Fire damage. The room refills with gas after one hour