Zorgo

Zorgo was a creature who has had a long lasting grudge against the Doctor. He has attempted to conquer time on 26 different occassions, but everytime the Doctor has been there to stop him.

When the Doctor and Clara landed on the Luminos Bridge on Myros, two robots greeted them and took a selfie with them - only for it to be sent directly to Zorgo who them identified him for his final plan to kill the Doctor. Zorgo then released a time dragon, which absorbed the time energy from the TARDIS, draining it into the dragon. The dragon then later blasted the two into Zorgo's lair, where he traps them in a time bubble - however despite the Doctor foiling his plans 26 times, the Doctor doesn't remember who Zorgo is. After explaining his different schemes, he realises he's old and dying and can't remember why he was trying to kill the Doctor anyway and let him go. The time dragon then fizzed and grew largely, spitting out vortex energy. One of these blasts hit Zorgo which caused him to become a baby again, and to be taken care by one of his robots. (COMIC: Zorgo the Terrible).