The former Kamen Rider Gaim stars are the latest Kamen Riders to return to the franchise.
Gaku Sano, who starred as Kota Kazuraba in the 2013-2014 Kamen Rider series, Kamen Rider Gaim, and Yutaka Kobayashi, who played Kaito Kumon/Kamen Rider Baron, will return to Kamen Rider Zi-O during its two episode Gaim arc, taking place throughout episodes 11 and 12.
During the episodes, a mysterious case revolving around the past and future mixing together will take place. Sougo suddenly transforms into Kamen Rider Zi-O Gaim armor and battles against Another Gaim. This causes the appearances of Kota Kazuraba, who became “The Man of Beginnings”. Elsewhere, Gates flies to Helheim forest and encounters Kaito. During the episodes, Woz will take his first steps towards betraying Sougo.
Source: Eiga Natalie