Ninjutsu, also used as ninpō (忍法) with its more modern definition, is a strategy and unconventional warfare, guerrilla warfare and espionage tactic said to be used by ninjas. ninjutsu; Shurikenjutsu is a separate discipline in some traditional Japanese schools that focus on kenjutsu, sōjutsu, bōjutsu, and other more nominal martial arts (taijutsu).