|This article is about a/an set of alternate forms in Kamen Rider Gaim.|
- "Den-O Arms: Iza Climax!"
- ―Transformation announcement[src]
Den-O Arms (電王アームズ Den'ō Āmuzu) is a Legend Rider Arms based on Kamen Rider Den-O's Sword Form. Accessed through the Den-O Lockseed or the Heisei Rider Lockseed channeling the Den-O Lockseed, this form's Arms Weapon is the DenGasher Sword Mode.
The Den-O Lockseed was created from Momotaros himself when the DenLiner he was piloting was taken out by a Shadow Line Kuliner sent by General Schwarz on behalf of the Underground Empire Badan during the Rider War between the Heisei Riders and Showa Riders. Ryo Murasame, had planned for this, however. Under the guise of Badan's Ambassador Darkness, Ryo collected the Rider Lockseeds before revealing himself as Kamen Rider ZX, using his Micro Chain to free the Lockseeds which were drawn to Kamen Rider Zangetsu, using his power to bring back the Kamen Riders, who had been waiting in the Helheim Forest, through the cracks back to Earth so they could all defeat Badan together.
- Kamen Rider Gaim (Kamen Rider Battle: Ganbarizing)
- Kamen Rider Baron (Kamen Rider Battle: Ganbarizing)
This form's Arms Weapon is the DenGasher Sword Mode.
- Kamen Rider Battle: Ganbarizing
- Heisei Rider vs. Showa Rider: Kamen Rider Taisen feat. Super Sentai (as Lockseed only)