Cardinal Arkendo was a young member of the Time Lord Parliament who assumed emergency powers over Gallifrey's High Council and helped bring an end to the Prydonian Academy Revolution (PROSE: CIA File Extracts) following the Master's murder of Lord President Slann. (PROSE: Birth of a Renegade) Afterwards, he feared reprisals from the Master, but there had yet to be any recorded attempts on his life by the Renegade by the time a Celestial Intervention Agency report on the Master's activities was written, which coincided with the era of the "Tremas" incarnation of the Master. (PROSE: CIA File Extracts)