Kamen Rider Revice S01 E26 Showdown! Farewell!? The End of Darkness and Light

"The hero and the demon are a tag team... in other words, the strongest!"

Following Genta Igarashi's sudden transformation into Kamen Rider Vail, the Igarashi siblings discover they are Giff's descendants through their father as their inner demons' connection to the original demon grows stronger.