Raidou is a nukenin ("missing shinobi") from the Mugen Tenshin clan, and one of the main antagonists of the Dead or Alive series. Raidou is the final boss of the first Dead or Alive. He is the older brother of Shiden and uncle to Hayate and Kasumi. A power-hungry warrior, he raped Shiden's wife, Ayame, which ended with her giving birth to Ayane, making the latter his daughter. He was killed by Kasumi during the first Dead or Alive Tournament in revenge for Hayate's supposed death. After Raidou's death, Donovan recovered his corpse and revived him as a cyborg in Dead or Alive 5 Last Round.