Quarren Maguire

Quarren Maguire was a Time Lord who had the ability to change reality with his own thoughts. He used a Chameleon Arch to turn himself human during the Last Great Time War.

As a Time Lord
Not much is known about Quarren as a Time Lord. Ollistra claimed he had achieved high grades while he was in the Time Lord academy, actually becoming one of the academy’s best students in its history.

Eventually, Quarren realised the power he possessed, and when the Time War came around, he turned himself into a human as he knew the Time Lords would want to use his power in the fighting, and believed they would abuse it when they had used it too often. (AUDIO: One Life)

Being Human
The Chameleon Arch Quarren used had created an entire life for him, even making it seemed that he had been married to Rupa for 20 years, both him and her completely convinced in this, when in reality, the circuit along with Quarren's powers had made this up entirely. The Eighth Doctor estimated that they had only truly known each other for about a small number of years. (AUDIO: One Life)

Still unaware about his true identity, Quarren and Rupa were onboard the Theseus when it was attacked by Daleks. They became part of the Doctor‘s group of survivors and joined him on a Dalek ship, which crashed on a jungle planet soon after leaving, the Theseus following swiftly. (AUDIO: The Starship of Theseus)