In this fourth and final chapter to the saga, the Great Twilight has begun and its curse has devoured the Erebonian Empire. It concludes the Erebonian Empire arc. Rean Schwarzer becomes unstable and his real self-starts to fade. His remaining friends therefore have to save Rean and the Empire from its impending doom.
The game continuing right after the events at the end of Trails of Cold Steel III, with members of Class VII waking up in the hidden village of Erin.