Tamasan was the pilot of Ollistra's Battle TARDIS.
Biography
Through her lives, Tamasan worked on the ranks of the Time Lord army besides Cardinal Ollistra during the Last Great Time War.
Working closely with her, Tamasan was very loyal to her cause, and willing to regenerate on battle if the situation required her to. (AUDIO: The Lords of Terror, The Famished Lands)
The Fourth Tamasan was the first incarnation of hers to meet the Doctor (then in his eighth body), on a jungle planet. (AUDIO: Echoes of War)
By the time she next met the Doctor, she had regenerated into the Fifth Tamasan, who was promoted from Commander to Major. (AUDIO: Planet of the Ogrons)
Shortly after, Tamasan regenerated once more, becoming the Sixth Tamasan. (AUDIO: State of Bliss) This incarnation, like her predecessors, worked the Eighth Doctor, (AUDIO: The Famished Lands) but also with the War Doctor. (AUDIO: The Shadow Squad)