Kwundaar

Kwundaar was the "god" who created the Source for the Trakenites and came from the Pre-Universe. Kwundaar attempted to trick the Doctor into giving Kwundaar the Source's power. He failed and was overcome by it. Before Kwundaar was destroyed, he sent out a signal for other Primeval beings to come back into the universe, and marked the Doctor for them. (BFA: Primeval)

Behind the scenes

 * Kwundaar is mentioned in a deleted scene from The Infinite Quest, as one of the beings which ruled the universe during the Dark Times.