In the Academy, the members of the Deca questioned and debated the profound wisdoms and Ancient Covenants of Gallifrey. The Deca included the First Doctor, Koschei, Ushas, Mortimus, Drax, (PROSE: The Quantum Archangel) Vansell, (AUDIO: The Rani Elite) and four others. (PROSE: The Quantum Archangel) The Fifth Doctor dreamt that other members were Rallon, Jelpax, Millennia, and Magnus.
Of these, Millennia and Rallon were made a part of the Celestial Toyroom, Jelpax became the Coordinator of the APC Net, (PROSE: Divided Loyalties) Vansell became head of the Celestial Intervention Agency, (AUDIO: The Sirens of Time) and the remaining six became renegade Time Lords.
The Fifth Doctor dreamed that the group represented the top rank of students in their class, (PROSE: Divided Loyalties) although the First Doctor was said to have not excelled academically. (TV: The Ribos Operation)