Casshan: Robot Hunter, known in Japan as Robot Hunter Casshern (ロボット・ハンター・キャシャーン, Robotto Hantā Kyashān) or simply Casshern (キャシャーン, Kyashān, romanized as Casshan in the official logo), is a 1993 OVA produced by Tatsunoko Productions and animated by Artmic (episode 1 to 3) and Gainax (episode 4). This series is based on Tatsunoko Productions' 1973 anime series Neo-Human Casshern. Casshan: Robot Hunter was originally released as a four-volume series in Japan.