A AU of kamen rider build, where Japan got split into four instead of three, the new fourth is extremely small, so it's often overlooked. Evol brought his little sister, who will use a Scorpion Faust bottle with the Transteam gun, but will use the Kamakiri(Mantis fullbottle, and Slicer Mantis(full bottle adaptor)) when she joins team Build.

A new rider, kamen rider Jawx, who uses the Jawx Tyranno(theropod head  themed bottle adaptor, which he uses multiple fullbottle with). He is an american teen who was raised in Japan.