Kid Niki: Radical Ninja

One day, in feudal Japan, Kid Niki, the most radical of all ninjas, is training in his ninja school. Suddenly, a bird flying by is shot by an arrow and lands at Niki's feet. Attached to it is a note saying that Niki's friend, Princess Margo, has been kidnapped by the evil stone magician. With a cry of "I'll help you!", Niki breaks through the wall of his school and sets off to rescue Margo.