Fourth PhDoctor is the fourth incarnation of the Alpha-Omegatrix's DNA sample of a Time Lord, also known as Gallifreyan, from Gallifrey.
Filled with wanderlust and a renewed curiosity toward exploring time and space, he left all ties of his previous incarnation's behind on Earth, setting off to travel the cosmos. He initially travelled with Destiny and Socium. They continued on their adventures until PhDoctor was summoned to a Celestialsapien-generated Gallifrey, necessitating that he leave Destiny and Socium behind as only Celestialsapiens and Time Lords were able to enter this Gallifrey.
PhDoctor then experienced visions of his past companions. He then saw visions of some of his past foes, all of those called to him. Losing his grip, PhDoctor fell to the ground. When his companions gathered around him, PhDoctor smiled, telling them that it was the end (of this incarnation), but the moment (of his regeneration) had been prepared for. He then regenerated into his next incarnation.
He looks like the 13-year old Richard, but with red eyes and the Alpha-Omegatrix on his wrist.
As a Time Lord, he has many powers. A binary vascular system, immunity to the vacuum of space, increased sound resilience, healing coma, radiation absorption, high electrocution immunity, telepathy, and regeneration up to 9 times, having 13 incarnations in all.
The Alpha-Omegatrix gives him what most Time Lords have, a sonic screwdriver, a psychic paper, and a TARDIS, Time And Relative Dimension In Space. This gives him a few controls over things, ebducing someone into seeing what he wants, and time-space travel.
He has fatal reactions to one of his hearts not working.
Although he can regenerate 12 times, after his 13th incarnation, Richard does not have access to him.
- His personality and death are that of the Fourth Doctor.