Qatal

Qatal, originally designated Subject 442, was a Sicari who was captured by Project Fury during the Last Great Time War and studied on Dreadnought Septima. He took old high gallifreyan word for stardust as his name. He was kept as the control in the experiment but mutated when the Septima entered the vortex to a creature more intelligent then the Time Lords according to Trellick. He was able to control time and used this to stop the ship was imploding. He was constantly curious. A Time grenade changed his biology. He wanted to know why Trellick didn't escape with him at the inital conflict, and eventually he learnt that she was worried that people would use him to destroy everything. (AUDIO: Hostiles)