Felix accompanied his father to Redcliffe, where Alexius had forced out Arl Teagan and manipulated the rebel mages into servitude. While Alexius was in the midst of negotiations with the Inquisitor, Felix feigned illness so he could pass a note to the Inquisitor, instructing them to go to the village chantry. Afterwards, Felix ditched his father and attended the meeting with Dorian. He reveals that his father is part of a Tevinter supremacist cult called the Venatori and are very interested in the mark on the Inquisitor's hand.
Should the Inquisitor choose to confront Alexius, Felix openly turns against his father and attempts to convince him to give up on his plans, but Alexius states that the Elder One can save him. As Inquisition agents kill Alexius' retainers, Alexius activates his time amulet in an attempt to change the past, Dorian interrupts him, accidentally sending both himself and the Inquisitor one year into the future.
In this bizarre future, where the Elder One dominates southern Thedas, Felix's condition had worsened. When Leliana takes him captive and Alexius identifies him, Dorian is mortified at what his former mentor had done to his son. Regardless of how the Inquisitor responds, Leliana slits his throat.
After defeating Alexius, the Inquisitor and Dorian return to the exact moment they left, and force the magister to surrender. Alexius bemoans his inability to save his son, but Felix states that he accepts his impending death.Felix soon returned to Tevinter and informed the Magisterium of what occurred at Redcliffe, but died soon after.