Kamen Rider Ryuki Season 1 Episode 25 Combining Ouja 

Shiro Kanzaki declares the battle is suspended. Shinji and Ren lose the ability to transform and can only do as Shiro commands while the monsters they contracted with attack them. And then Reiko finds Asakura's little brother, Akira. Akira, who confesses that his older brother is frightening, is persuaded by Reiko and the others but...