Sebastian

Sebastian is an injured man recuperating at Britain's Wound Healing during Ultima IV.

Description
Although the events which landed him in his current state were never revealed, Sebastian had somehow gained knowledge of Mondain's lingering influence in Britannia, and would beg the Stranger to help cleanse the world of it, directing the hero to ask after stories of a still extant artifact at the pub in Buccaneer's Den.

Trivia

 * In a document purported by scholars Robert de Main and Carlotta Stein to be the journal of the Avatar, Sebastian is not named specifically, but a man young fitting his description is mentioned as resting on a pallet behind a curtained alcove at Wound Healing, having suffered an injury to his side.
 * In the Nintendo port of Ultima IV, Sebastian has been replaced by an unnamed patient, who exhorts the Stranger to seek the eight Runes and eight  Stones, rather than mentioning Mondain's skull.