Zoria

A mysterious agent with unknown superiors, going by gender-neutral pronouns, continually used the Time Fracture to find "very specific people" and went to "very specific places". (WC: Is anyone receiving these transmissions?)

Biography
After UNIT Sergeant Robert Dudley was left stranded in Elizabethan England after travelling through the Time Fracture, (WC: This is Sergeant Robert Dudley., Dudley here.) he spent five years in the court, where he had noticed a "mysterious agent" who had been "collecting various parts", though he wasn't sure what they were doing or building. He spoke about other information he knew about the agent in a transmission to the UNIT Black Site, even though he was unsure if it still existed. (WC: Is anyone receiving these transmissions?)

Behind the scenes
In Time Fracture, which is not considered a valid source in this wiki, this agent is revealed to be the Time Lady Zoria who is gathering the pieces for the Temporal Disruptor that be used to reset the universe so that the Time Lords can rule over the new one.