Dojjen

Dojjen was a Manussan historian and Ambril's predecessor as Director of Historical Research. He believed that the Mara had not been destroyed and would someday return. He learned the rituals needed to defeat the Mara and taught them to the Fifth Doctor. (TV: Snakedance)

The Doctor later mentioned a desire to catch up with Dojjen. (AUDIO: The Cradle of the Snake)