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Klefing gathers up keys until it has attached one to each of its rings. When fully equipped, it lets out fumes from its face in joy. This smoke smells of rust, copper and other metals.

Getting up close to a Klefing will give you a chance to observe, through its thin skin, the toxic gases swirling inside. 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.