In Kamen Rider Decade, I Was Pulled into a Chat Group from the Start

The protagonist transmigrates into the world of Hikari Studio, replacing Tsukasa Kadoya. When he steps outside, he discovers that it's the Kuuga world with Onodera, but he can't transform into Decade? How is he supposed to continue his journey?

Just then, he binds to the Ultimate Enhancement System, which lets him enter an enhanced state for a short time. As Decade, the effect is doubled, turning him into Complete Form.

Then he's pulled into some kind of multiverse chat group**?

You're still twenty thousand years too early: You're just a Kamen Rider, barely over a meter tall. One kick and... WTF, why are you as tall as me!

Never let talent go to waste, Cao Mengde: Great one, would you join my army as a general? Xu Chu, Dian Wei, you two can get lost!

Bargain-Day Baldy: Someone actually caught my normal punch!

Tsukasa Kadoya: I'm just a Kamen Rider passing through. Give me... Never mind, you're about to be gone anyway, so you don't need to remember.

Natsumi Hikari: Omnipotent Tsukasa Kadoya, yet somehow his photography is exceptionally bad!

This novel and its characters are entirely fictional. Any resemblance is purely coincidental. Please do not imitate.