Dr. Elias Proctor, Ph.D., was a Terran citizen and a renowned cyberneticist.
He was a member of Pei Shan-wei's team in Operation Ark, and was the one who came up with the plan to use Nimue Alban's PICA to serve as an immortal "advisor" for the humans of Safehold. He also hacked the cybernetic avatar's software to overwrite the restraints on an uploaded personality's maximum service time. (OAR)
The Holy Writ painted him as the fallen Archangel Proctor and follower of the treacherous Shan-wei, responsible for temptation and forbidden knowledge. (HFAF)