Lich

In life, the frost-mage Ethreain (not yet a Lich) had used the threat of destructive ice to enslave entire kingdoms. His subjects, aided by a few desperate magicians, eventually grew bold enough to ambush him. Armed with enough charmed rope to bind him forever, they tied the frost mage to adamant weights and dropped him in a pool known chiefly for being bottomless. It wasn't. He only fell for a year or so before an outcrop snagged him. There he rested, dead but undecaying, until the geomancer Anhil thought to verify the legend of the supposedly bottomless Black Pool. Anhil's plumbline snarled with the ropes that bound the drowned magician, and up he hauled an unexpected prize. Thinking that by rendering the dead undead, he could question the Lich about the properties of the pool, he removed the bindings and commenced a simple rite of resurrection. Even the descendants of Ethreain's enemies were long forgotten by time, so there were none to warn Anhil against imprudence. But he learned the error of his judgment almost immediately, as Lich threw off the shackles and consumed him.