Wandering around in Relics, Chrono and the rest encounter the vanguard of an Apostle, Gastille. At the same time, Taiyou battles against Valeos and the Zeroth Dragon on the surface.

Kai and Arata searches for the secret base of the Apostles, while Makoto meets up with Kamui and Misaki to sneak into the Apostles` secret research facility. The one who awaits them is the one who became a Diffrider, Wakamizu.