When the Breach opened, Blackwall kept the people of the Crossroads safe from demons with no expectation of reward. While Blackwall kept the demons at bay, the villagers fled with supplies from their farms as they fled the danger but were eventually robbed by bandits. Once Blackwall discovered that the bandits robbed the fleeing innocents, Blackwall became furious and rallied some of the farmers in order to hunt the bandits and recover the stolen supplies. Blackwall told the farmers that while demons and Blights were his responsibility, the farmers would need to learn how to defend themselves against such thieves on their own. Inspired by his leadership, the farmers willingly followed Blackwall into battle.
Should the Inquisitor choose to find Blackwall in the Hinterlands, they arrive to find Blackwall training a trio of conscripts to fight off bandits, who attack shortly after. After fending off the bandits, Blackwall sends the conscripts off and is questioned by the Inquisitor over the disappearance of Ferelden's Wardens. He admits that he knows nothing about other Wardens, as he has been on the road without contact, but refuses to stand idle if his order was involved in Divine Justinia V's death. Believing his aid could make a difference in restoring the peace, Blackwall offers to join forces with the Inquisition.
Note: Blackwall must be recruited before meeting Hawke and the Warden at the Tevinter ruins in the Western Approach. Following this exchange, he is no longer available.
If Blackwall accompanies the Inquisitor in the siege of Adamant Fortress, he can reason with the Warden warriors by reminding them of their duty.
Back at Skyhold following the events of Here Lies the Abyss and Wicked Eyes and Wicked Hearts, Blackwall will take the Inquisitor out for a drink at the Herald's Rest. As they drink, Blackwall solemnly tells the Inquisitor the tale of how as a boy, he ignored a bunch of urchins abusing a stray dog begging for food. He expresses his guilt about how he ignored the dog's suffering and allowed injustice to be done. He tells the Inquisitor that they could make the world better but people choose not to out of expedience. Blackwall then concludes "There's always some dog out there. Some f*cking mongrel that doesn't know how to stay away." If the Inquisitor is in a romance with Blackwall, he does not bring up the story in this scene. Instead, The Inquisitor and Blackwall return to the barn and share a romantic encounter in the barn's loft. Later that night, the Inquisitor will wake up and discover Blackwall is gone.
When the Inquisitor returns to Skyhold following the previous scene, it is revealed that Blackwall has disappeared. An Inquisition messenger shows the Inquisitor a crumpled note, suggesting that Blackwall intends to attend the execution of a man called Mornay in Val Royeaux, accused of taking part in a massacre at the order of his captain, Thom Rainier. At the execution, as Mornay stands before the noose, Blackwall steps up to the platform, admitting to have given the order to Mornay, revealing his true identity as Thom Rainier and impersonation of Blackwall. He is arrested by the guards and brought to the Val Royeaux prison.
If the Inquisitor visits him in prison, they have a chance to question Rainier. He reveals his true past as a captain in the Orlesian army, his part in the massacre of the Calliers, the circ*mstances of the real Blackwall's death and his assumption of his identity. When he learned that Mornay had been captured, Rainier couldn't let him take the fall for his crime.
If the Inquisitor chooses to free Rainier, the latter is judged back at Skyhold. The Inquisitor has the decision of either setting him free, making him serve the Inquisition against his will or turning him over to the Wardens once Corypheus has been defeated. If forced to serve the Inquisition against his will, Rainier will be ordered by the Inquisitor to continue masquerading as Blackwall and as a Grey Warden in order to give the Inquisition a more advantageous facade - much to Rainier's disgust. If pardoned, Rainier decides to atone by dedicating his life to the Inquisition. If pardoned or sent to the Grey Wardens, Rainier will prefer to be called "Blackwall" since he has become accustomed to being called by the name and now thinks it more of a title that he should live up to.
If Blackwall's disapproval gets too high (assuming he's not forced to serve after Revelations), the next time the Inquisitor visits Blackwall in Skyhold, he will express disappointment in the Inquisition and the Inquisitor's choices. Blackwall will accuse the Inquisition of being a gang of thugs serving a self-serving tyrant and will leave the Inquisition. If in a romance with the Inquisitor, he's willing to wait to see if the Inquisitor will change but if she doesn't, he states he cannot allow her to lead him down this path and eventually breaks up with her as well as leaving.
Blackwall will greatly disapprove of banishing the Wardens at Adamant, but he will opt to stay with the Inquisition and will not leave so long as his approval remains at a respectable value.
It is revealed in Blackwall's companion quest that he did not actually complete the Joining and is therefore not truly a Grey Warden. Should the Inquisitor choose to send Blackwall to the Wardens, however, it is implied that he will undergo the Joining.
