A mercenary in feudal Japan trained in martial arts
Secrets of the samurai: 
a survey of the martial arts of feudal Japan, Tuttle Publishing, ISBN 978-0-8048-
1684-7... [DOC] [TLE] Ninja with Scott Adkins | Martial Arts Action Movies - DVD\'s - Blu-rays [PAR] In feudal Japan, A Ninja was a mercenary, trained in the martial arts, espionage 
... Outlawed in the 1600's, the tradition was kept alive in secret, the deadly art... [DOC] [TLE] Ninjutsu Training | Ancient Art of Stealth - Advance Martial Arts ... [PAR] Ninjutsu is a Japanese martial art originally used in espionage.