Karate for Life is the closing chapter that Oyama needs, but the ending still leaves many possibilities. The films never chronicled the rise of his fighting style or the other events that occurred. The film transpires over a small amount of time when Oyama was a thug and bodyguard stretching to his moments with children. Oyama is a great father figure and I myself wouldn't mind getting my ass handed to me by him for a righteous discipline.
Oyama engages in a ridiculous and often humorous job of professional wrestling. He is part of a team that points jests towards the Japanese. Due to Oyama's fighting spirit, he cannot fix a match and gets over his head with mobsters and sharks. The scenes of professional wrestling fixate on the American military in the crowd hollering a fierce chant warranting death. Surely the Japs think little of us, but portraying us as rabid animals is taking it a bit far.
From what I've written on the previous films, not much changes. The film plots stay perfectly linear and the director doesn't like to sample change. I can't say much more than I've previously written but the Oyama trilogy is one of the best martial arts series' ever made. It's unfortunate that his saga wasn't continued past three films and that Sonny Chiba has aged past his prime.