The true identity of Cath, who attacked Arthur, is that of a beast tyrant who was once created from chaos. Merlin, who has parted company with the Seven Deadly Sins, confronts Cath alone to protect Arthur. Arthur also drew his sword to confront Cath, but he was about to collapse before Cath's psychic attack. The Seven Deadly Sins and Elizabeth came to the aid of Merlin and the others in a pinch. Will the chaos engulf the world? The final battle of the Seven Deadly Sins begins...!