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Klefbat fly in the darkness of night, jingling the keys on their tails together to make noise for echolocation. They make their perch within locked rooms, so it is advised to look for Klefbat nests if your keys are missing.

While living in pitch-black caverns, their eyes gradually grew shut and deprived them of vision. It never lets go of a key that it likes, so people give it the keys to vaults and safes as a way to prevent crime.