Ryuken, also known as Master Ryuken, is a fictional character from the anime series Hokuto no Ken (Fist of the North Star). He is the 63rd successor of the Hokuto Shinken martial art and the adoptive father of Kenshiro, the series' protagonist. Ryuken is depicted as a wise and powerful martial artist who plays a crucial role in the early parts of the series. His teachings and principles significantly influence Kenshiro's journey, as he imparts the legacy and responsibility of Hokuto Shinken to him. Ryuken's character embodies the themes of discipline and sacrifice.