Black Samurai(Black Samurai‪)‬

When terrorists butcher his sensei, a samurai takes vengeance in blood
On leave in Tokyo, American GI Robert Sand is shot trying to protect an old man from a quartet of drunk American soldiers. As Sand passes out, the old man springs on his tormenters, beating them senseless with frail, wrinkled fists. He is Master Konuma, keeper of the ancient secrets of the samurai, and Sand is about to become his newest pupil. Over the next seven years, the American learns martial arts, swordplay, and stealth, becoming not just the first black man to ever take the oath of the samurai, but the strongest fighter Konuma has ever trained.
One night, two dozen terrorists ambush the dojo, slaughtering Konuma and his students as the first step in a terrifying assault on world peace. Though he cannot save his sensei, Sand escapes with his life and a gnawing hunger for vengeance. All he has is his sword, but his sword is all he needs.