Ninja
In the history of Japan, a ninja (忍者, ninja) was someone specially trained in a variety of unorthodox arts of war. These included assassination, espionage, and other martial arts.
In the Japanese culture, they were usually trained for dangerous missions. Although their exact origins are still unknown, with some historians speculating about some Chinese origin or influence, it is known that they appeared in 14th century feudal Japan, and remained active from the Kamakura to the Edo period. Their roles may have included sabotage, espionage, scouting and assassination missions as a way to destabilize and cause social chaos in enemy territory or against an opposing ruler, perhaps in the service of their feudal rulers (daimyo, shogun), or an underground ninja organization waging guerilla warfare.
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