Envy demons are one of the rarer varieties of demon. They are consumed by the need to not only emulate mortal beings, but become them.
Envy demons are equal parts arrogance and cowardice. They isolate their victims to study them at length, seeking to become them. Once the demon is satisfied it knows its chosen subject, it takes on their form, leaving the poor soul to rot. Envy is never satisfied, however. The demon's bottomless cravings to be more—more powerful, more skilled, more inspired—cause it to seek fresh prey, leaving a trail of stolen identities behind.
This transition is when Envy is weakest, for it is vulnerable as it moves from body to body, slavishly copying the habits of the old identity until it finds another mortal to mimic. This is why I am writing this down. The man cowering before me wanted so badly to know what a demon thinks, wants, feels. He would document everything. Everything. He resists, a prisoner in his own home, but I already know this. I hunger for knowledge as he does. As I will.
Envy demons are among the most insidious spirits of the Fade. They seek out hosts of significant merit, specially those who hold a position of leadership, then study them. They may spend weeks doing so, carefully observing their target's mannerisms and interactions with others. Once they have learned enough to emulate their target's psyche, they assume their target's physical form and identity. The original person becomes almost impossible to recognize from the demon, whom is a perfect replica of its target. Its mannerisms, tics, and opinions are identical to those of the original person. The unfortunate soul is usually quietly disposed of thereafter, so to eliminate any possibility of controversy.
Despite their ambition, envy demons are also cowardly. They are cautious not to alert those they have deceived to their true identity. They usually flee if they are exposed, retreating behind arcane barriers of their devising.
According to Knight-Templar Delrin Barris, the rank and file of the Templar Order aren't trained on confronting envy demons since they are so rare. Veteran members of the Order know well enough to fight them, and can nullify their defenses if provided with sufficient lyrium.
The Lord Seeker Lucius Corin makes use of a Envy demon pawn to masquerade as him and lead the Templar Order while he led the Seekers of Truth to their doom, as the Seekers wouldn't conform to the use of Red Lyrium. The Demon appeared in Val Royeaux to officially announce that the Chantry no longer held any control over the Templars and leaves after proposing an alliance to the Inquisitor
If the Templars are recruited into the Inquisition...
Should the Inquisitor take 'Lucius' up on its offer it is revealed that the entire meeting was a elaborate trap: to purge the order of the few Templars not affected by the red lyrium and to kill and replace the Inquisitor. Towards this end, the demon begins gathering information on the Inquisitor by sending its subordinates to their deaths against them in order to gather information on their leadership style.
Following this, the Demon drags the Inquisitor into the Fade where it attempts to further goad them in order to learn more information. It forces the Inquisitor to kill illusions of their allies as well as taunting them with images of what the Inquisition will look like under its rule. The Inquisitor is aided by a Compassion Spirit named Cole, who guides the Inquisitor to resist Envy. Eventually, during their confrontation, Envy assumes the Inquisitor's form, frustrated with Cole's interference. Cole then appears, distracting Envy, allowing the Inquisitor to punch Envy and returned to the physical world.
With its ploy having failed, Envy reverts to its true hideous form and retreats behind a barrier. The Inquisitor and the templars who were not corrupted yet then team up to fight Envy's Red Templars. After the barrier is dispelled, The Inquisitor and their group confront the Envy demon in the courtyard aided by Cole, whom partway through the battle assumed The Inquisitor's form to fight the group. Once the demon is finally dead the remaining templars are either conscripted into or made allies of the Inquisition.
The impostor Lucius Corin is revealed to be an envy demon in Cassandra's personal quest. After the demon flees Therinfal Redoubt, it can be hunted down by Bull's Chargers during an operation with the assistance of Josephine or Leliana.
If the Mages are recruited into the Inquisition...
See alsoCodex entry: Envy Codex entry: Envy's Dogma
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