Ultimate Key (5e Equipment)
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Wondrous item, legendary
Unlock any door with the Ultimate Key!
Unlock. This key can be used to unlock any nonmagical lock, regardless of type of lock or designated key. When this key is held near any lock, it flashes bright and the end of the key molds into a key that will open the lock.
However, the Ultimate Key cannot lock a door. If this is attempted, the door will simply remain unlocked.