Dominus, from Ultima Underworld
Dominus is a mage of the Seers of the Moonstone and the local artifact expert.
The Avatar met him in Ultima Underworld I on the sixth level of the Abyss. Dominus was willing to identify all kind of magical items and artifacts for a small fee in gold (usually around 10 gold pieces). If the Avatar's lore skill was low, his services would be needed often.
Later, Garamon rescued him when the volcano erupted.