Ambril

Ambril was a Manussan historian who replaced Dojjen as the Director of Historica Research. He believed the Mara had been destroyed.

in 3426, he took Lon and Tanha on a tour of the caves, where they encountered the Fifth Doctor.

When the Doctor came to his office, he disregarded the Doctor's warnings about the Mara. To show him that the ancient legends were nonsense, he showed the Doctor the Six Faces of Delusion, saying that he could't believe a legend that couldn't count right. When the Doctor pointed out that the sixth face of delusion was the wearer's own, the infuriated Ambril told the Doctor to leave.

Lon later took Ambril back to the caves and manipulated him into returning the Great Crystal to it's original place by threatening to destroy the priceless historical artifacts that were hidden in one of the caves. He and Lon returned to Ambril's office to inform Tanha that the Crystal would be returned during the ceremony.

He was later present when the Mara was destroyed by the Doctor. (TV: Snakedance)