Like most RPGs in recent years, Dragon Age: The Veilguard has more to offer players than just its main story; among many hidden bosses is the Betrayal of Felassen, a high-level boss that offers unique rewards. The Betrayal is a part of the “Heart of Corruption” questline that’s found early on in Veilguard but will take you most of the game to complete. The specific sub-quest that the Betrayal is part of is entitled “Gate of Deep Sorrows,” and you’ll find it in the Converged City in the Crossroads.