Alone for years in the wild, Marlin returns a changed man - Hardened by trial tempered by faith, and carrying the weight of visions yet to come. As Vortigern's fragile alliance crumbles and Saecsen power surges, Merlin must choose when - and how to shape the fate of Britain.

War brews, loyalties splinter, and Merlin's past erupts—threatening to destroy the fragile future he fights for.