Kougane

"I am the God of the New Generation!"

- Kougane, in its male form, telling Kouta who "he" is

Kougane (コウガネ), or Kogane in different publications, is Kamen Rider Mars (仮面ライダーマルス), who is the main antagonist in Kamen Rider Gaim: The Great Soccer Match! The Golden Fruit Cup!. It later returns in the series finale as the female Kamen Rider Jam (仮面ライダー邪武 [ジャム]), serving as the series' final villain.

Golden Fruit Cup
Kougane is the manifestation of an artificial Golden Fruit created by the Over Lords in the past. When an experiment by Ryoma goes wrong, Kougane awakens and kills Ryoma. Kougane's existence causes the Armored Riders to lust after each other for the "Golden Fruit". Slowly, the Armored Riders start to kill each other off as Kougane masquerades as Yuya to get to Kouta. The deaths of the fallen Armored Riders strengthens Kougane's "Golden Ringo" Lockseed. When it is revealed that he is not really Yuya, Kougane transforms into Armored Rider Mars and defeats Kouta. Corrupting Gaim into Gaim Yami, the two go after Lapis. However, Ryugen, Baron, and Marika interfere, with Lapis disrupting the mind control on Kouta. Kouta transforms into Gaim Kachidoki Arms and chases Mars in a fight that ultimately allows most of the deceased Riders, whose heart was not fully corrupted like Sigurd and Duke, to return to aid Kouta. Mars emerges with a flaming horse and is defeated by the Armored Riders as the world returns back to normal, also resulting in Lapis' disappearance.

Post-Helheim Invasion
Kougane survives his encounter in the movie and returns after seven months has passed since Helheim plants and Inves were removed from Earth. Taking the form of a locust, he possesses a teenage girl as leverage in case if he's at a disadvantage. Using the Black Ringo Lockseed, he is able to assume the form of Armored Rider Jam, a substantially weaker form than Armored Rider Mars, due to the energy in the Golden Ringo Lockseed being completely drained after his original defeat. He seeks out the other Armored Riders for forcing him into disgrace only to realize that Lapis had altered everyone's memories to make it appear as if it were a dream. Taking on Kougane first is Jonouchi, honoring the late Ryoji Hase by transforming into Kurokage. However, Kougane easily defeats Jonouchi without any effort. Next in line to fight against Kougane is Mitsuzane, who puts up a fight despite being at a disadvantage with Jam and Grasshopper Monster against him. Kougane reveals that he's using a human body as his vessel, causing Mitsuzane to cancel his transformation. However, Kouta appears, revealing that he left one loose end and that's Kougane. Kouta destroys the Grasshopper Monster in his wake and forces Kougane out of the girl's body. Kougane is killed by Mitsuzane and Kouta's Rider Kicks as they pushed his own Darkness Au Lait back at him. At the end of the series, the girl who was possessed by Kougane is teaching the two kids Kouta and Kaito had helped out a long time ago about the sacred tree and dancing.

Arms
Like with the other Lockseed-using Kamen Riders, Kamen Rider Mars/Jam's forms are called Arms (アームズ).

Devices

 * Sengoku Driver - Transformation device
 * Lockseeds - Gives access to Mars/Jam's Arms changes, depending on which lock is used.

Weapons

 * Mars:
 * Arms Weapons - Weapons that come with the Arms:
 * Sword Bringer - One of Mars Golden Arms' personal weapons
 * Apple Reflecter - One of Mars Golden Arms' personal weapons
 * Jam:
 * Musou Saber - Jam's side weapon in every single one of his forms
 * Arms Weapons - Weapons that come with the Arms, besides the Musou Saber:
 * Daidaimaru - Jam Darkness Arms' personal weapon

Portrayal
Kougane is portrayed by Kataoka Ainosuke VI (六代目 片岡 愛之助). While under the guise of Yuya Sumii, he is portrayed by Hiromi Sakimoto (崎本 大海). In the series' finale, a girl who possessed by Kougane is portrayed by Honoka Ando (安藤 穗乃果). As Kamen Rider Jam, he is voiced by Atsushi Ono (斧 アツシ).

As Kamen Rider Mars, his suit actor is Yasuhiko Imai (今井 靖彦), who also serves as the suit actor for Kamen Riders Bravo and Kurokage (Ryoji Hase). As Kamen Rider Jam, her suit actor is currently unknown.

Legend Rider Lockseeds

 * The following Legend Rider Lockseeds are styled for Mars/Jam, as well as Zangetsu:
 * Stronger - "Aku wo Taoese to Ore wo yo Bu!"
 * ZO - "Daijizen Neo Seimeitai!"
 * Agito - "Mezamero, Sono Tamashii!"
 * Ryuki - "Tatakawanakereba Ikinokorenai!"
 * Hibiki - "Tatakikome Kiyome no Oto!"
 * Momotaros - "Ore Sanjou!"
 * Fourze Cosmic States - "Minna no Kizuna de Uchuu wo Tsukamu!"