Astonishing ninjutsu + gunfight!! Takashi Horie's all-out western ninja action is now in book form for the first time!! Ninjas invade western movies!? Synopsis The chief is a ninja and a gunman!? Koga Elementary School is the only survivor of a secret battle with Iga ninjas Goro is invited by the Indians and travels to America. Kogoro, who discovers his roots in the bullet-ridden West, decides to become the ``black wild bull'' of the Seminar tribe, which is attacked by cavalry.