Butterfly Knives are weapons used by the Black Dragon mercenary Kano in Mortal Kombat. He very often uses his Butterfly Knives in combat, whether he throws them at the opponent or uses them in hand-to-hand combat.
The criminal Kano uses these single-edged knifes to slit the throats of anyone who gets in his way. They have been used throughout the Mortal Kombat series. Three of Kano's signature moves have to do with the Butterfly Knives, such as the Knife Throw, the Blade Swipe, and the Blade Spin.