Miggim, from Ultima VII Part Two
The Avatar first met him in Ultima VII Part Two in the Inn of the Sleeping Bull. Since all of the Monks had teleport powers, it was unknown why he was there. However, while he avoided telling the Avatar too much (not yet the right time), he did warn the hero that there would be a future assassination attempt - which later proved true when Selina double-crossed the Avatar.
Miggim was later found on Monk Isle, where he finally spoke about his job as the librarian and that it included transcribing books. He went quite into detail about some of Xenka's prophecies of the Avatar's arrival and the end of the world - although he admitted that most of the prophecies were hard to understand, thanks to the meddling of his predecessors.
Miggim also openly admitted that he was on Thoxa's side; like her, he felt that more direct action was needed.
Later, after receiving the Amulet of Balance from Karnax, Miggim told the Avatar how he'd found it in the cellars and that the instruction scroll sadly hadn't survived the years. However, he had found the hint to use it on a Serpent Gate.