NEW YORK TIMES BESTSELLER!The ninja were the true embodiment of budo, the warrior spirit. Rather than using techniques of assassination to protect themselves, ninja relied on their senses, and on an acute awareness of their natural surroundings, In fact, ninja avoided unnecessary conflict, and used weapons such as knives and swords only as a last resort. These are the true techniques of ninjutsu, and the art in which the ninja unrelentingly trained.