The Machine that Opens Doors, especially when you have a slightly bad key, or simply the Bad Key Machine, is a key item in EarthBound. It allows certain doors to be unlocked without a working key.
The Bad Key Machine is obtained from Maxwell after Jeff finds the bent key to be broken and unusable when he tries to open the lockers in the Snow Wood Boarding House. It can open any door, and is used to escape the underground area in Threed. After this usage, it has no more purposes. It can be used to try to unlock Dungeon Man while the entrance is still locked as well as the door to the traveling entertainer shack in Onett during the alien invasion, but it will only state that the key does not fit those doors.
Prices
EarthBound
Buying
Selling
Not for sale
Cannot be sold
In-game description
EarthBound
•
The "Machine that Opens Doors, especially when you have a slightly bad key" machine.