The Son of Decade will now start his own journey but before he could go to the new rider worlds he must first go to other ones and train until he is ready to go there, will he be able to make his parents proud and be the new savior of the multiverse.
Many years after the events of Kamen Rider Build, Sento would have a son, Shinji, and would give him the Build driver, and Bottles.
Shinji would later move to, New York, and become it's protector.