Trave

 was a Time Lord who was part of Celestial Intervention Agency and was part of the war against Omega.

She was tasked with killing Ace and Narvin. After the timelines were changed she was tasked with guarding the border between Monan Host and Gallifreyan space. She was shot by Gaal after he was found out to be a traitor. She regenerated into a male form. He then discovered Ace's dead body floating about in space. (AUDIO: Enemy Lines)

Trave later regenerated into another male incarnation and at some point, became a general. (AUDIO: Celestial Intervention) He ultimately proved himself to be loyal to the High Council and manipulated events to get Valerian into power. (AUDIO: Desperate Measures)