The secret data entrusted by Takumi Katsuragi revealed the contents of a file known as “PROJECT BUILD”. Katsuragi’s picture was within it, including his own research data on the system operations of the Build Driver. But why was Katsuragi, the founder of Faust, creating the Build system? There is an intense conflict developing between Sento and Ryuga, over if Build’s existence can be considered as “justice” or as a “weapon”… (Source: kamenrider.fandom)