Hokuto Shinken
In the story, Kenshiro is the rightful successor of an ancient art of assassination called "Hokuto Shinken", which allows Kenshiro to defeat his adversaries through use of hidden meridian points. Through the course of the original manga, Kenshiro fights against various ruffians who threaten the lives of the post-apocalyptic survivors, as well as numerous rival martial artists, including his three honorary brothers trained in the art of Hokuto Shinken.