Luxury mansions commonly keep a pack of Arcaki on the grounds to serve as guards against thieves. Arcaki attach themselves to doors, allowing trusted people into the building they guard, whilst launching Flamethrowers at those they don't know.
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. This fleet-footed Pokémon is said to run over 6,200 miles in a single day and night.
