Made edits to clarify a few points.

The Dark Sages are human Dragon Cultists, fanatics who worship Yddrog and believe, as he does, that humanity is inferior to him and deserve to be totally enslaved to his rule.

The Chosen Champions, the players, belonged first to the Archon of Regret before succumbing to Yddrog a thousand years later. How this came to be will be left to the imagination for the time being. My current headcanon is that Regret did not grant them the ageless functions of her power, so they died of old age and were since resurrected with Yddrog.

The Princess of Aetherion is dead. She was sacrificed on an altar to bring the dragon back. This only worked because she was a direct descendant of Regret and possessed a small portion of her power. Her death is the incident that brought the rage of the Aetherion Kingdom down upon the monsters.