Chest of Reflection (5e Trap)
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Chest of Reflection
Magical seals on the chest reflects damage done to it or its locks. It was developed in response to paranoid adventurers attacking any and all containers in fear of them being mimics.
If a creature within 60 feet deals damage to the chest or its lock by the means of an attack or spell, it receives the same amount of damage as force damage. The Armor Class of the chest varies with its material, although the effort needed to enchant the chest means it made at least out of stone. (Armor Class 17, Refer to DMG, page 246 for other materials for the chest) Due to being reinforced with magic, the chest has 50 hit points and is resistant to all damage from non-magical attacks, in addition to being immune to poison and psychic damage. The damage reflected is calculated before applying the resistance of the chest. The lock is integrated in the chest. The DC to pick the lock with a set of thieves' tools is 15. The seals on the trap can be noticed by any creature capable of sight or touch interacting with the chest. A successful Intelligence (Arcana) Check against a DC of 15 is needed to identify the function of the seals. A dispel magic spell cast on the chest dispels the seals.
This trap is both used in combination with a domesticated mimic somewhere else in the dungeon or on its own.