Mitsuzane Kureshima

Mitsuzane "Mitchy" Kureshima (呉島 "ミッチ" 光実 Kureshima "Mitchi" Mitsuzane?) is a member of the Kureshima Family and is the younger brother of Takatora Kureshima. Mitsuzane, initially a member of Team Gaim and a close friend of Kouta Kazuraba becomes Kamen Rider Ryugen (仮面ライダー龍玄 [リュウゲン] Kamen Raidā Ryūgen?, lit. "Dragon Mystery") to protect his team and his friends during the Inves Games.

Hidden from his friends is his Kureshima background where he was forced to live in an environment with a heavy burden from his brother, who wants him to exceed in life, likewise the same from his father, Amagi Kureshima. Mitsuzane eventually joins his brother's goal of trying to save humanity from the Helheim Invasion through Project Ark, but when his brother allies himself with Kouta, he becomes a victim of a coup d'état causing Mitsuzane to blame Kouta for his brother's "death" and causing his crush, Mai Takatsukasa to lash out at him. Through Kouta and Mai's "death", Mitsuzane is unable to see his other friends eye to eye and views himself as someone who is incapable of their friendship.

For a short time, Mitsuzane takes up the mantle of Kamen Rider Zangetsu Shin (仮面ライダー斬月 真 [ザンゲツ シン] Kamen Raidā Zangetsu Shin?, lit "True Slaying Moon") until it is destroyed by Ryoma Sengoku and also became the lethal Kamen Rider Ryugen Yomi (仮面ライダー龍玄・黄泉 [リュウゲン・ヨミ] Kamen Raidā Ryūgen Yomi?, lit "Dragon Mystery Underworld"). At the end of the TV series, Mitsuzane is the last person with the Sengoku Driver and strives to become a hero in Kouta's stead now that he and Mai are gone.