Jack the Knife

Jack the Knives are enemies encountered in the game Wario: Master of Disguise. Their name is a pun of "jackknife," a type of knife, and the song Mack the Knife. They are formed from the rage of a lifetime's worth of butter-spreading and other mundane uses for knives. They are giant knives about the size of Wario, with eyes and "teeth"; they jump out of tables of the S.S. Caviar and try to attack Wario.

In-game description
''These dull and rusted knives are fueled by their own rage over a lifetime of butter-spreading and chicken kiev-slicing. Rusted and dull, they know neither remorse nor pity.''