This section contains spoilers for: Dragon Age: Inquisition.
The forces of Corypheus seize the Shrine of Dumat to serve as a major stronghold in their war to exalt their new god.
If the Inquisition recruits the Mages: Samson uses the Shrine of Dumat as his personal fortress and sets up his friend, the Tranquil; Maddox, there to research ways to improve and maintain Samson's unique red lyrium armour. Eventually the Inquisition discovers the location of the Shrine and launches an attack. Samson flees while Maddox and several Red Templars remain behind to delay the Inquisition and destroy any information that could be used against them.
If the Inquisition recruits the Templars:
Calpernia, leader of the Venatori, desires to train at the Shrine, but Corypheus says only Dumat's faithful can enter. The Inquisition learns of the Shrine using an altered memory crystal planted in Calpernia's camp and figure that Corypheus is hiding something from Calpernia. They fight past the demons guarding the Shrine and find at the center MagisterErasthenes, Calpernia's former master, held by a binding ritual of Corypheus. Erasthenes reveals that Corypheus plans on using a more powerful version of the ritual to bind Calpernia when she becomes "The Vessel". Afterwards, the Inquisitor can either end his suffering or leave him for Leliana's agents to question.