If you control 20 or more Samurai, remove the 20 of them with the highest Force from the game. You do not need them, for you are your twenty strongest! If this removed 20 Samurai, you win the game.
"Contestation of the Mantis Clan's status is now impossible," Kiharu said solemnly. "The Kami have accepted Yoritomo among them, just as the clans did generations ago."