The Ancient Dragon is, according to Vittorio, the burning calamity that would occur should all four Void
Mages gather together. Much bigger than a regular dragon, he has the ability to emit Miasma in order to form an anti-magic barrier around itself. This Miasma also has the power to control other dragons, with two known exceptions: a dragon which is being controlled by Vindálfr manages to retain its sanity, although by opening its Third Eye, the Ancient Dragon is able to bypass this; and Tabitha's familiar, Sylphid, as a Rhyme Dragon, is unaffected by the Miasma.
The Ancient Dragon has as its objetive to destroy everything, including its rivals, the Void Mages. Although Void Mages are the Ancient Dragon's weakness, they are also its source of strenght; when the Ancient Dragon ate Vittorio, it enveloped itself into a rock cocoon-like shell, emerging as a more powerful form afterwards.