|This article is about a/an form in Kamen Rider Zi-O.|
GenmArmor (ゲンムアーマー GenmuĀmā) is a Kamen Rider Genm-based form accessed using the Genm Ridewatch, invoking Kamen Rider Genm's Action Gamer Level 2. When summoned, it is projected in a holographic Rider Gashat and does Genm's signature pose before dispersing to attach to the user. GenmArmor's Proto Gashat Shoulders (プロトガシャットショルダー Puroto Gashatto Shorudā) are modeled after Proto Mighty Action X Rider Gashats, and depending on whether it is used by Zi-O or Geiz, its visor spells out "Genm" (ゲンム Genmu) in katakana or "Genm" (げんむ Genmu) in hiragana respectively.
After the Genm Ridewatch was dropped by King Kuroto Dan, Geiz tried to use GenmArmor in 2016 to stop Dan's first attack as Another OOO. Despite destroying him with a Critical Time Burst, this was unsuccessful in eradicating Another OOO as Dan had made the contract in 2010 and the year marked on his back only appeared to read "2016" due to a crack, as well as Genm not being the same power as that of OOO.