This is a strikingly beautiful trap. When placed in a darkened room, you can see a faint and ominous glow coming from the chest even before testing the latch. Opening the chest reveals faint laser lines criss-crossing back and forth across the mouth of the chest, lines that might be missed completely in a well-lit room but become bright if you blow smoke or mist into the box. Breaking a beam with your hand, or bump one of the carefully-positioned mirrors that bounces it from source to receiver and you trigger an alarm.
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