The Ninja Master, or simply known by the "Masked Ninja", is the evil leader of the crime syndicate Neo Zeed, and the main antagonist in The Revenge of Shinobi. He attacks Joe Musashi with his long hair and also uses it as a boomerang. He's also the first boss to display evil laughter during the fight.
After Joe defeated Zeed, the Masked Ninja persona was taken up by another, and through him Zeed had returned, more powerful than ever as Neo Zeed. The Masked Ninja returned as the leader of the criminal organization called Neo Zeed. He appeared in the last level where Joe confronts him in a final showdown. The Ninja Master trapped Joe's bride, Naoko in a cell trap where it can kill her. Joe defeated the Ninja Master and rescues Naoko and reunites with her.
- The Ninja Master in the bottom picture is Nakahara from the first Shinobi game. The one with similar hair in Shinobi III is not Nakahara and is a boss named Byakushishi.