Long before time began, when reality was but an idea, a force of unparalleled power dominated the void.
It was unthinking, lacked imagination, and existed for only one purpose: to create balance in the universes that were yet to come.
It tried to divide itself between the parallel universes of reality as best it could, but knowing that it could not split into infinite pieces, it had to create a solution.
In the end, the force relegated its power to a single one of the universes. This one would be perfect. Balanced. Complete equilibrium.
In the force's wisdom, it created horrors unimaginable. Creatures and monsters were born that would kill, slice, and devour. Beings of such terror that their proper names are lost in the stars. Only those giant balls of burning gas could possibly survive uttering the names of these creatures now.
However, there must always be balance. The force from the void concentrated its abilities to create the most perfect counterweight to the nightmares that now ravaged the galaxies of this reality.
Billions of years later, on a planet inhabited by a highly advanced civilization, this perfect balance was achieved.
And he is called the Doctor.