Sourcery

A sourcerer—magic itself, rather than a mere wizard—is born the eighth son of a dying mage, and his birth throws Unseen University's wizards into a power struggle they were never built to survive. Rincewind, the Disc's most cowardly and least competent wizard, is dragged back into danger by a barbarian's hairdresser daughter and a hapless would-be hero, and finds himself the only one willing to stand against young Coin's rise before it drags the world into open magical war.