[Monsoon]

I think a lot of basic tokusatsu / shounen / superhero elements like poses, announcing special moves, and implementing forms or transforming to use different skills all basically come from wuxia books and movies from the 1950s and 1960s. Kamen Rider definitely took it a specific extreme, though, and made it its own.

Unrelated question: do I need to watch Kuuga before Agito? I'm still sampling the different Heisei Riders. I know that the two shows are connected somehow but I'm a little hesitant to watch a direct sequel without checking out its predecessor.