Raidou

Raidou (雷道, Raidō) is a Runaway Shinobi from the Mugen Tenshin Ninja Clan, and the final boss of the first Dead or Alive. He is the older brother of Shiden and paternal uncle to Hayate and Kasumi.
A power-hungry being, he raped Shiden's wife, Ayame, which ended with her giving birth to Ayane, making the latter his daughter. He was later killed by Kasumi during the first Dead or Alive Tournament in revenge for Hayate.