Fintor

Fintor is a mage imprisoned by Tyball.

After the Avatar freed him in Ultima Underworld I from his cell on the seventh level of the Abyss, talking with him revealed that the imprisonment had made him somewhat mad and paranoid against anyone else. However, despite trying to not reveal it, in his rambling he did reveal the secret of hidden doors in the crypts and something important at the bottom of the chasm of fire.