|This article is about a/an set of alternate forms in Kamen Rider Gaim.|
- "Fourze Arms: Seishun Switch On!"
- ―Transformation announcement[src]
Fourze Arms (フォーゼアームズ Fōze Āmuzu) is a Legend Rider Arms based on Kamen Rider Fourze, but it was partially summoned from space when it passes through the Crack, which is accessed through the Fourze Lockseed. Accessed through the Fourze Lockseed or the Heisei Rider Lockseed channeling the Fourze Lockseed, this form's Arms Weapon is a choice of the various Module Weapons.
The Fourze Lockseed was created in the world of the Warring Period through the combination of a Helheim's Fruit provided by the Priestess of Fate and the Rocket Astroswitch left behind by Kamen Rider Bujin Fourze. Among a gathering of Legend Rider Arms, Fourze Arms was assumed by Armored Rider Zangetsu who used it to fight against Bujin Gaim's monsters before regrouping with Ryugen W Arms, Baron OOO Arms, and Kamen Rider Beast Hyper to destroy the Utsubokazura Kaijin.
- Kamen Rider Zangetsu (Kamen Rider × Kamen Rider Gaim & Wizard: The Fateful Sengoku Movie Battle)
- Kamen Rider Fifteen (Heisei Rider vs. Showa Rider: Kamen Rider Taisen feat. Super Sentai)
- Kamen Rider Gaim (Kamen Rider Battle: Ganbarizing)
- Kamen Rider Ryugen (Kamen Rider Battle: Ganbarizing)
- Kamen Rider Marika (Kamen Rider Battle: Ganbarizing)
- Kamen Rider Gaim
- Jimber Ride Wear
- Kachidoki Ride Wear
- Kiwami Ride Wear
- Ride Wear (Drive Arms ver.)
- Kamen Rider Baron
- Kamen Rider Ryugen Yomi
- Kamen Rider Zangetsu
- Ride Wear (Watermelon Arms ver.)
- Kamen Rider Gridon
- Kamen Rider Kurokage
- Kamen Rider Bravo
- Kamen Rider Knuckle
- Kamen Rider Bujin Gaim
- Kamen Rider Mars
- Kamen Rider Kamuro
- Kamen Rider Zangetsu Shin
- Kamen Rider Duke
- Ride Wear (Dragon Energy Arms. ver)
- Kamen Rider Sigurd
This form's Arms Weapon is a choice of the various Module Weapons.
- Rider Ten Billion Volt Break (ライダー１００億ボルトブレイク Raidā Hyaku Oku Boruto Bureiku): Fifteen charge the Billy the Rod before he unleasing a 360 degree electricity based turn slash on the target.