Kamen Rider Zi-O is the title character and main protagonist of the tokusatsu series Kamen Rider Zi-O, not Kamen Rider Ryuki. He is a time-traveling hero who becomes the Heisei era’s final Kamen Rider, using powers linked to past Riders to fight enemies that threaten history. As Sougo Tokiwa, he dreams of becoming a king, and his journey centers on whether he will become a benevolent ruler or a destructive demon king.