The Bad Key Machine (known fully as "Machine that Opens Doors, Especially When You Have a Slightly Bad Key) is an item in EarthBound. It is the design of Winters inventor Maxwell Labs, given to Jeff Andonuts after he gives him a bent and unusable key. The Bad Key Machine is then used to open lockers and obtain their contents for Jeff's journey to Threed, where he must rescue Ness and Paula. The machine also proves useful in unlocking the door to the secluded room where the two are held captive.