The Great Boss of Black Satan is the leader of Black Satan and the main antagonist of the first half of Kamen Rider Stronger. He is the source of the Satan Bugs that allow Black Satan to control others.
He is yet another incarnation of the Great Leader.
As with most incarnations of the Great Leader, the Great Boss of Black Satan was voiced by Gorō Naya.
With his Satan Bugs, the Great Boss sought to gain control of the world by using them to possess and control people.
After Mr. Titan was killed, the Great Boss of Black Satan brought in General Shadow to replace him in Black Satan's Japanese branch. Later on though, the Great Leader had Titan revived, causing a rivalry to spark between Titan and Shadow.
The Great Boss eventually attempted to replace General Shadow with Dead Lion, causing the General to desert Black Satan. Stronger also discovered the Great Leader's hiding spot and went to confront him, destroying him with a Stronger Electro Kick.