Bronus, from Ultima Underworld
Bronus is a mage of the Seers of the Moonstone.
The Avatar met him in Ultima Underworld I on the sixth level of the Abyss. Bronus asked the Avatar to return a magic book to Morlock under the condition to not look into it. The Avatar promised it, and returned the book to Morlock, thus passing the first part of the test of Honesty.
Later, Garamon rescued him when the volcano erupted.