Kougane

Kougane is the manifestation and embodiment of the Golden Fruit of Helheim and the main antagonist of the Kamen Rider Gaim movie ''Kamen Rider Gaim: Great Soccer Battle! Golden Fruits Cup! He later reappears in the final episode of Kamen Rider Gaim'' as the final antagonist of the entire series.

He is portrayed by kabuki actor Ainosuke Kataoka VI.

Kamen Rider Gaim: Great Soccer Battle! Golden Fruits Cup!
Kougane was the manifestation of an artificial Golden Fruit created by a Femushinmu scientist. His awakening accelerated the extinction of the Femushinmu Race by causing them, so he was sealed away by the Overlord Inves Lapis.

Kougane was later freed after Ryoma Sengoku broke his seal. Kougane caused the Armored Riders to fight each other for the Golden Fruit in order to strengthen his Golden Ringo Lockseed. He also assumed the guise of Kouta Kazuraba's friend Yuya Sumii in order to get close to him. His disguise is eventually lifted, at which point he assumes his Armored Rider form and attacks Kouta. After defeating Gaim, Kougane mind controls him into Gaim Yami to assist him in defeating Lapis.

However, Lapis undoes Kougane's corruption of Gaim and Mitsuzane, Kaito and Yoko show up to assist him. With the assistance of the Armored Riders who died, the four defeat Mars and return the world to its original state.

Kamen Rider Gaim "Transform! And to the Future"
However, Kougane secretly survived and re-emerged after the Helheim Forest was cast from Earth. Possessing a girl, Kougane transforms into Kamen Rider Jam to go after the Armored Riders to get revenge on them for his defeat. After Hideyasu Jonouchi tries and fails to beat him, Mitsuzne Kureshima shows up and transforms into Kamen Rider Ryugen. Ryugen beats down Jam, but Jam reveals he is possessing a girl as a host and that if Ryugen defeats him the girl will die, causing Mitsuzane to back down. Kouta Kazuraba then shows up and forces Kougane out of the girl's body. Kouta and Mitsuzane then fight Kougane together and finish him off with the combined power of their Rider Kicks.

Trivia

 * Kougane's actor Ainosuke Kataoka VI chose to portray him because he was a fan of the Kamen Rider series when he was younger and hoped that young viewers of the series might recognize him in his kabuki shows when they got older.