Archdemon

Archdemons are the Old Gods manifested in the form of powerful and terrifying dragons and tainted by darkspawn. They possess an intelligence far beyond the average dragon and are purely evil creatures. Most of the time, the darkspawn are organized as a simple hive-mind, concerned only with expanding the horde. They rarely appear on the surface, except in raids and small invasions. Similarly, the Archdemon rarely fights on the surface during Blights unless direct intervention is necessary, though through the hive-mind, the Archdemon communicates with and commands the entire horde whether in their presence or not; Grey Wardens often "hear" the Archdemon in their dreams, veteran Wardens even claiming to understand parts of the Archdemon's speech.

A Blight begins when the darkspawn find and taint an Old God, who then unites them into a great horde and unleashes them onto the surface in a wave of darkness and destruction. The Archdemon is their leader, and a Blight will not end until the Archdemon is destroyed.

Before the events of Dragon Age: Origins, there had been four previous Blights, led by the Archdemons Dumat, Zazikel, Toth and Andoral, respectively.

Since the dwarves managed to fend off the darkspawn invasion after the First Blight, no Archdemon has led a Blight against them. Instead, the dwarves consider the Blight to be something of a respite, as all darkspawn activity is focused on the surface.

Involvement
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 * Urthemiel in Dead Trenches.png

The Archdemon in Dragon Age: Origins is revealed to be Urthemiel, the Tevinter god of beauty. In Dragon Age: Origins - Awakening, the Mother reveals that it became an Archdemon due to a botched attempt by the Architect to turn it into a Disciple.

It is first seen during the Warden's Joining ceremony, then in the Warden's dreams after first leaving Lothering. While traveling to the Dead Trenches, it makes its first 'live' appearance (though from a distance, not within range of confrontation or targeting).

The Warden discovers on the eve of the Battle of Denerim that the Archdemon must be killed by a Grey Warden. If killed by anyone else (as Riordan explains) its soul will escape to the nearest darkspawn (who are soulless), making it practically immortal (barring the impractical eradication of every darkspawn in existence). However, if a Grey Warden strikes the killing blow, the soul will assail that Warden's taint - causing both souls to be destroyed. As the senior Grey Warden present, Riordan acknowledges his duty to make the first attempt.

After this revelation, Morrigan waits in the Warden's bedroom to offer a deal. The premise here is that a Warden's taint will transfer to the pregnancy, and this will lure the escaping soul to be bound into the unborn child, rather than the standard mutual destruction with its slayer.

The Battle of Denerim
When the Warden reaches Redcliffe, they are informed the Archdemon has been sighted near Denerim. Thus Ferelden's capital becomes the site of the final battle. This is where the Warden will call all allies that have been gained previously.

The Archdemon is sighted some time after reaching Denerim, flying over the city followed by a charge of human soldiers. It is next seen from the Elven Alienage as the Warden leaves, after either killing or avoiding the Hurlock General there. The Archdemon flies overhead and destroys the bridge, making backtracking impossible for the 'primary' party.

At this point Riordan will be atop a tower dealing with his own group of darkspawn. The Archdemon swoops past the tower, and Riordan jumps onto its back, maintaining his position by stabbing his sword into various points in its body. The Archdemon attempts to 'skim' a tower, forcing Riordan to jump onto its right wing. It then flies directly upward, sending Riordan into a fatal fall, but not before he inflicts a massive wound which forces it to land atop Fort Drakon, where the remaining Warden(s) can finish it off.

When the Warden reaches the top of the fortress, the Archdemon is busy demolishing soldiers. This leads to the final fight of the Fifth Blight. }}