|This article is about a/an set of alternate forms in Kamen Rider Gaim.|
- "Donguri Arms: Never Give Up!"
- ―Transformation announcement[src]
Donguri Arms (ドングリアームズ Donguri Āmuzu, lit. "Acorn Arms") is an alternate acorn-based armored Medieval Squire form of Armored Riders. Accessed through the Donguri Lockseed, this form's Arms Weapon is the Donkachi, while the helmet the Rider wears is the Dome Casque (ドームカスク Dōmu Kasuku) with the Nut Eye (ナットアイ Natto Ai) visor. While it is the default form of Armored Rider Gridon, it can also be used by other Riders.
- Armored Rider Gridon (Main user; Gaim Episodes 5-7, Sengoku Movie Battle, 10, 11, 25, 32, 34, Golden Fruits Cup!, 39, 41, 44, Final Stage)
- Armored Rider Gaim (Kamen Rider Gaim: Great Soccer Battle! Golden Fruits Cup!)
- Armored Rider Kurokage (Kamen Rider Battle: Ganbarizing)
- Armored Rider Knuckle (Kamen Rider Battle: Ganbarizing)
- Armored Rider Proto Gridon (Kamen Rider Zangetsu: -Gaim Gaiden-)
- Kamen Rider Gaim
- Jimber Ride Wear
- Kachidoki Ride Wear
- Kiwami Ride Wear
- Ride Wear (Drive Arms ver.)
- Kamen Rider Baron
- Kamen Rider Ryugen
- Kamen Rider Zangetsu
- Ride Wear (Watermelon Arms ver.)
- Kamen Rider Bravo
- 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
- Kamen Rider Marika
- This form's Arms Weapon is the Donkachi.
After Gridon activates his Sengoku Driver's Squash function, he spins at high speeds with the Donkachi held out. The spinning forms an acorn projection before Gridon knocks the opponent with a high-velocity hammer slam. Performed in episodes 6, 32
An unnamed Armor Part strike is seen in episode 41, where Gridon's Donguri Armor Part back into its normal nut form, making Kamen Rider Bravo throwing Gridon himself into Kamen Rider Zangetsu Shin, allowing them to leave from the battle.
- "Gridon" was a named pun of Donguri, however, Jonouchi dislikes this name as he become a Kamen Rider.