Knightmare Frames, or simply Knightmares, officially designated as the Humanoid Autonomous Armored Knight, are a form of mecha in the Sunrise anime series Code Geass: Lelouch of the Rebellion. Knightmare Frames are humanoid war machines in the anime series Code Geass: Lelouch of the Rebellion. In the series, they were developed by the Holy Britannian Empire. Unveiled during the invasion of Japan, Knightmare Frames are almost exclusively used in place of the practically obsolete main battle tanks. The name "Knightmare Frame" is a play on the words knight, mare and nightmare.