Junsei Motojima

Has the world suddenly split into four? Keiwa Sakurai, Neon Kurama, Michinaga Azuma, and Tsumuri are flung into different worlds. And for some reason, a different Ace exists in each of the four worlds. The cause seems to be from the "World Doomsday Game" started by the staff from the future. In light of this crisis, the mysterious Cross Geats appears. Just what will happen to Ace and his friends?

Houtarou is summoned to a parallel world by Houou Kaguya Quartz to protect it from the evil Hundred. Kaguya seeks power from past Kamen Riders and wants to make Houtarou "gorgeous" to gain his help.

Houtaro Ichinose and his friends continue their search for the Chemies, and Ace Ukiyo and his friends confront the Jyamato, who has appeared again, when suddenly the "Strongest Level 10 Chemy", X Wizard appears. Its mysterious magical powers have transformed Keiwa Sakurai and the others into the form of Chemies!

Houtaro and his friends are suddenly attacked by Geryon. As they struggle against enemies that appear one after another from a space-time gate, they discover that enemies have been sent from the future! To protect the present and the future, Houtaro and Rinne travel through time and space to the devastated future. Thus the final battle, with everything on the line, finally begins!

"Alchemy" is a pseudo-science that attempts to create "gold" from various different combinations. One experiment to do so artificially brings to life a race of creatures, and the story revolves around an era where these experiments were being conducted in secret. In the story, the artificial lifeforms known as the "Chemy", are made to imitate things that exist in the world...

An exemplary student and a troublemaker delinquent are drawn together after the former discovers the latter's secret, leading to an intimate relationship between the two. (imdb)