Saga no Mamoru

Saga no Mamoru (サガマモル) is a major character within the lore of Kamen Rider Nio. The first person to receive the Flames of Ari during the Kamakura period, he lead mankind against the threat of the Enmi before sealing them in their own realm. He is the ancestor of Era Saga and the main protagonist of Kamen Rider Nio: Episode "Zero" - The Harsh Battle Alone.

During his time, he was known as Bushin Rider Nio (武神ライダー仁王), though he is also referred to as Kamen Rider Old Nio (仮面ライダー仁王先).

Portrayal
He is portrayed by Masashi Taniguchi (谷口 賢志), who previously played Jin Takayama in Kamen Rider Amazons.