The Renegade was an evil man who had once had all the powers of The Doctor. For crimes against humanity, he was stripped of his powers and sent to a prison at the beginning of time. He's gulty of killing twelve million people and he was only able to be caught because after the genocide, he decided to fest, by drinking all the wine in existence.  
From prison, he was somehow able to set in motion events that threatened the present day: by telepathically convincing Earth of the danger that the Human race was for her, turning the planet into a doomsday weapon with the only porpuse to kill his inhabitants. 

He told The Authority that he would only fix things if the powers of The Doctor were returned to him for one hour. Jeroen, to save the world, gave the powers back. The Renegade fix the problems he had caused, but attacked the Authority and he was easily beating them all.  
He was only stopped when the full powers of The Doctor hit him (He had been getting it back little by little.) as long as Jeroen love for everything
that exist. The new emotions brought the Renegade into a guilt induced breakdown, that allowed Apollo to finally kill him.