The Hojo clan was a warrior clan that ruled the Kanto region from the 15th to 16th century. Supporting their efforts to defeat enemies and maintain control was a mysterious group called the Fuma ninja. Their leader, Fuma Kotaro, is described in historical documents as a monster, and may have been the reason why they were so feared. We'll look at how the Fuma ninja took over castles and also guarded them for the Hojo clan.