Astrolabus

Astrolabus was a renegade Time Lord who stole the Book of the Old Time, as well as the treasures of a dozen worlds.

Biography
Astrolabus stole some star charts from Voyager by travelling to Antarctica and threatening the Sixth Doctor with a gun so that he handed them over.

Astrolabus fled, with the Doctor giving chase. Returning to his TARDIS, which was in the form of a lighthouse, Astrolabus told the Doctor how he had helped Alexandria develop into a crossroads for aliens. The city grew great under him and he helped built the world's first lighthouse there.

The Doctor identified him as the thief who stole the book. Astrolabus made the Doctor imagine he was falling from the lighthouse when he was on the ground, gripping the edge of a table. The Doctor escaped and Astrolabus pulled a lever atop his lighthouse. It turned into a rocket and took off. (DWM: Voyager)

As Professor Astro Labus, he set himself up as president of the Zyglot trust, while as the swami Astral Arbus, he employed Akkers to capture Zyglots. When the Sixth Doctor and Frobisher caught up with him, he pulled the Whifferdill with him into his cabinet. (DWM: Polly the Glot)

Astrolabus had the stolen star charts tattooed onto his body. The Doctor tracked him down and captured him. Voyager then retrieved the charts by removing Astrolabus' skin, killing him. (DWM: Once Upon a Time Lord)

A book known as the Insidium of Astrolabus was among the evil or arcane works which were kept in the Master's TARDIS library. (PDA: The Quantum Archangel)