Shuriken

A shuriken is a Japanese concealed weapon used by samurai and ninja, thrown or wielded as a hidden blade to distract, injure or misdirect an opponent. Its exact origin is unclear because the practice of shurikenjutsu was traditionally kept secret, though the earliest documented school teaching it, Ganritsu Ryu, was established in the 17th century. Shuriken take two main forms: bo-shuriken, straight four sided iron or steel spikes roughly 12 to 21 centimeters long, and hira-shuriken or shaken, flat metal plates with pointed edges often built around a central hole. They served as supplementary weapons to the sword in a samurai's arsenal, aimed at exposed targets such as the eyes, face, hands and feet.