Okada, Nizou

岡田似蔵

A blind hitokiri employed by Takasugi. He aims to destroy everything in the world, much like Takasugi. His swordsmanship is so advanced that he can slash an opponent before they see him draw his blade. However, Gintoki broke Nizou's sword during their first encounter. Nizou later returns and severely wounds Katsura and Gintoki with a demonic sword, 'Benizakura', which transforms his arm and fuses the blade to it. The Benizakura acts as a parasite, gradually taking over Okada's body, causing him to eventually become nothing more than a crazed monster. Because of the sword, his body has undergone several modifications. He later reveals that his entire upper torso features similar cybernetic enhancements. He is eventually defeated by Gintoki. Although his fate is unknown, he is presumed dead due to the effects of the Benizakura.
His name is roughly based on one of the hitokiri of the Bakumatsu era, Okada Izō.