Shogun Assassin (1980)

Shogun decapitator, lone wolf, ronin. Travels with his son, Daigoro, in search of the Shogun that is paranoid of his skills. In the attempts to kill Lone Wolf, Shogun's ninja kills his wife and leaves him to care for the boy. Lone Wolf swears that Shogun will pay for his deeds. Revenge and justice drive Lone Wolf through Japan's forests and deserts in search of vengeance.