Araugauthos

Araugauthos (The Bluetalon ) is an old blue dragon that was imprisoned in the ruins of Undermountain by Halaster Blackcloak. She later escaped from imprisonment.

Background
In autumn, 1369 DR, Citadel Amnur in Amn was attacked by an unknown red wyrm. Soon after, Araugauthos attacked the red wyrm by ripping through its wings with her claws, causing it to fall to its death, becoming impaled on sharp rocks. Araugauthos questioned the troops at Citadel Amnur for news of Faerûn since her imprisonment and left after two tendays, taking most of the contents from the lair of the red wyrm. She traveled to the lair of her mother, Iryklathagra where she aids in the defence of the lair & acts as a decoy to would-be dragonslayers. Her mother rewards her well for the service & the two get along very well.

Iryklathagra surmises that the reason for Halaster's imprisonment of her daughter dates back to when she herself was a wyrmling & looted an abandoned tower that belonged to the Mad Mage.