Finnian Valentine
Finnian Valentine was a Barvan from Konoi VII who had been severely affected and rewritten by the Time War in two different ways.
First, his marriage changed from being to a woman to being with a man; second, the species that killed his family changed from being the Daleks to the Time Lords. He wanted to use a terrible weapon when his world was invaded and seeked to bring an end to the Time War.
After he was killed by a temporal weapon, two versions of him from both timelines were left behind as the timelines shattered around him. the War Master and Leela, who had been tasked by Narvin and Romana II to discover information about the weapon that he wanted to use, found one version of Valentine tied up in a bunker, the other watching him.
Interrogating a version of Valentine each, the Master and Leela eventually learnt that the weapon was a power source on Arcking. Both versions of him were ultimately killed by the Master. (AUDIO: The Devil You Know)