Ninja was a covert agent or mercenary in feudal Japan. The functions of a ninja included espionage, deception, and surprise attack. Their covert methods of waging irregular warfare were deemed dishonorable and beneath the honor of the samurai. Though shinobi proper, as specially trained spies and mercenaries, appeared in the 15th century during the Sengoku period (15th–17th centuries), antecedents may have existed as early as the 12th century.The FamiLane Collection’s premium T-shirt should be a big part of any kids’ wardrobe. It wears rough and tough for kids who play the same way. Ideal for playing outside or sitting quietly doing homework, the premium T-shirt from the FamiLane Collection is as versatile and durable as it gets.