Major character in the various Well World sagas, by Jack L. Chalker. Little is actually known about Nathan Brazil, except that he is immortal, is the only person (until later in the books) who has root access at the Well of Souls, and is a lying scoundrel.

At various points, he has claimed to be God, the last Markovian technician, the Wandering Jew, and a poor schmuck who got suckered into being the guardian of the Well. He has the capability to alter reality in a controlled fashion when in the Well, including setting other people up with this power, and rebooting the universe.

Since he is a product of an earlier universe, and the caretaker, the Well, which runs the universe, will not allow him to die.