This individual has no known canonical name. While the information presented is canonical, the individual described lacks an official name, thus the title is conjecture.
Prior 1 (The Ark of Truth) is a male Human from the Alteran Home Galaxy and a Prior of the Ori.
This Prior tortured Vala Mal Doran for intel, though not successful. It can be assumed he lost his powers after the Ark of Truth was activated. (SG1: "The Ark of Truth")