- Yusuke Onuki (Daughter of Lupin) as Kaima Todoroki/Kamen Rider Seeker, the "strongest assassin" standing in front of Geats and Revice's way
- Tetsuhiro Ikeda (TRICK) as Korath, the mysterious game master of the Desire Royale
- Ryo Horikawa (Dragon Ball series) and Hiroshi Kamiya (Attack on Titan, Uchu Sentai Kyuranger) as Validero and Izanagi respectively, they are two unidentified lifeforms who attacked the Igarashis and are aiming for the demon that lives inside baby Koshiro, the Igarashi sibling's new baby brother.
Directed by Takayuki Shibasaki (Kamen Rider: Beyond Generations), and written by Yuya Takashi (Kamen Rider Geats) & Hanta Kinoshita (Kamen Rider Revice), Kamen Rider Geats x Kamen Rider Revice MOVIE Battle Royale is set for a December 23rd release.