Zachariah

Zachariah is an astronomer and mage living in Moonglow at the time of Ultima V. He is a source of useful information, namely how to use the positioning of the comets in the night sky to predict where a Shadowlord will appear. He can also tell the Avatar who to speak to concerning the Moongates, which can lead to the discovery and use of Moonstones.

Ultima V: Lazarus
In the Lazarus version of the game, Zachariah is also something of a recluse. He used to be quite well known and popular amongst the mage communities of Moonglow and the Lycaeum—his knowledge and teachings were highly sought after—but shortly after the Oppression gained power in the City of Honesty his opinions, particularly about the nature of three comets, started to be met with derision, then hostility. He sealed himself up in his tower with his studies and his observatory. As far as the residents of Moonglow can tell, he never walks through its doors.

Zachariah was introduced to the Resistance by none other than Mariah, who came to his tower one night seeking refuge from the city guard. With the help of Malifora and Nilrem they managed to establish a smuggling route with Buccaneers' Den to keep the Lycaeum supplied with reagents. Zachariah funds the smuggling route but is slowly running low on gold. Malifora can't risk the exposure due to her being a former member of the Great Council, and Nilrem is getting paid for his help almost as much as Captain Dalgrin is.

Quests

 * The Avatar can choose to tell Zachariah how the Moongates function, once the knowledge is discovered.
 * A designer reports one quest is as yet undiscovered/unreported here.