Also known as: ライダーマン
Enemy, and later ally, of Kamen Rider V3. Also known as the "Avenging Demon".
A former scientist of the Destron organization framed as a traitor, Jouji Yuki takes up the name of Riderman to eliminate V3 and clear his name.
Riderman is not named the 4th Kamen Rider until he sacrifices himself to redirect a missile bound for Tokyo.
His distinguishing features include his mechanical right arm and helmet that exposes the lower half of his face.