This article is about a/an movie-exclusive villain in Kamen Rider Fourze.

Groundain (グランダイン Gurandain) was the blue car-like older brother of the Kyodain. As Kyodain's human identity, Harumi Saeba (冴葉 晴海 Saeba Harumi) is the general manager of the OSTO Legacy.


Groundain was created along with the other Space Ironmen by Professor Blink. However he and his sister Skydain went rogue and attacked the professor. The professor siphoned their power and kept them sealed within the Space Core. In order to get their powers back and start their plan, Groundain posed as the general manager, Harumi Saeba of OSTO Legacy and recruited the Kamen Rider Club to deal with Black Knight and Inga Blink and power down XVII. With the Space Core powered down, the Kyodain regained their forms and attacked the Club before going on with their plan to use XVII to destroy humanity.

Kamen Rider Fourze in Cosmicstates managed to stop their plan by warping the orbital laser back at XVII, ceasing its functions. The Kyodain then attack the powered down Fourze and Meteor. When it seemed hopeless, Fourze gained the power of the Fusion Switch and Fusionstates. The Kyodain assumed their vehicle forms as Fourze rode on his Machine Massigler, before Fourze made the finishing blow with Fusionstates' Limit Break, destroying the Kyodain.

Super Hero Taisen Z

Groundain (Super Hero Taisen Z)

Groundain revived as a member of Space Shocker.

The Kyodain are later revived as members of Space Shocker. However, due to their sense of honor and desire to fight GavanIcon-crosswiki, the two are destroyed by Space Ikadevil for acting against their cause. Kamen Rider × Super Sentai × Space Sheriff: Super Hero Taisen Z


Groudian body


  • Height: 234 cm
  • Weight: 232 kg

Groundain is armed with a powerful cannon built into his chest called the Grounbuster X (グランバスターX Guranbasutā Ekkusu). Groundain also has the ability to use his Cosmic Energy to summon Dustards like the Horoscopes.



Grouncar-Skyjet Combination

The combination of Grouncar and Skyjet

Groundain is also able to transform into a car-like form known as the Grouncar (グラウンカー Guraunkā). In this form, he can combined with Skydain.


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