Finis

Finis is a Time Jacker responsible for the creation of Another Zero-One and the main antagonist of the Kamen Rider crossover movie Kamen Rider Reiwa: The First Generation.

History
Finis surfaced some time after Swartz's defeat and rewrote the history of the World of Zero-One to prevent the Daybreak Town Incident from happening. She gave Will the Zero-One Anotherwatch, granting him the power to transform into Another Zero-One and causing Aruto Hiden to lose his powers as Zero-One in 2019. With his Another Rider powers, Will murdered Korenosuke Hiden several years before his death in the original timeline and usurped control of Hiden Intelligence, commanding the HumaGears to go out and exterminate the humans.

Trivia

 * Finis is the second Time Jacker to serve as the main antagonist of a Movie War crossover film, following Tid in Kamen Rider Heisei Generation FOREVER. Like Tid, it is unknown what connection Finis has to Swartz. Interestingly, while Tid was the villain of the final Movie War of the Heisei era of Kamen Rider, Finis is the villain of the first Movie War of the Reiwa era of Kamen Rider.