Killer Instinct is a fighting game developed by Rare and published by Midway and Nintendo. Initially released in arcades in 1994, and rumored to use an "Ultra 64" hardware engine, in reality the proprietary arcade hardware was co-developed by Rare and Midway. The game received a high-profile launch on the Super Nintendo, as well as on the Game Boy. Its popularity led to a sequel, Killer Instinct 2.
Killer Instinct 2 (commonly abbreviated KI2) is a 1996 arcade-only fighting game developed by Rare Ltd., licensed by Nintendo, and manufactured by Midway. Like its predecessor, the game features two 8-way joysticks with six buttons each for attacks (three punch and three kick), allowing for both a single player mode or a two player versus mode. A modified version of KI2 appeared on the Nintendo 64 as Killer Instinct Gold in 1996.