The Rider Worlds have begun to merge, causing untold chaos as enemies from throughout the Heisei era run rampant! At the same time, the Ride Watches begin to turn to stone! Could the two events be connected? With Tsukasa’s help, Sougo and Tsukuyomi travel to Tsukuyomi’s own past to learn of Swartz’s true goal, while Woz and Geiz face-off with the Roadmude reaper himself, Machine Chaser!