In the Hall of the Two Truths, at the place of the weighing of the heart, beside the great scales upon which the heart of the dead is laid against the feather of Maat, there crouches a creature of three forms: she has the head of a crocodile, the forequarters of a lion, and the hindquarters of a hippopotamus. She was called Ammit, the Swallower, and her function was simple and dreadful. If the heart of the dead, when set against the feather, was found to be heavy with falsehood — if Thoth declared the verdict of injustice — then the dead would be cast to her, and Ammit would devour the heart, and with it the soul, and the unjust would be no more.

She does not appear in any ordinary myth; she has no story save the story of the judgment. Her three forms were each a creature that the Egyptians knew to be deadly to humankind: the crocodile of the river, the lion of the desert, the hippopotamus of the marsh. To meet her was to meet the natural death thrice gathered, and to be unmade. The vignettes of the Book of the Dead nearly always show her at the foot of the scales, ready and patient; sometimes she is portrayed in detail, sometimes only by a single waiting muzzle.

Yet Ammit was not herself a power of evil. She did not pursue the dead nor seek them out; she was simply the consequence of an unjust life, set in place by Maat herself. In her presence the doctrine of judgment was made absolute: the soul that had not lived in truth would not endure beyond the body. To the Egyptian sensibility, this was not damnation but obliteration — a cleaner and starker fate than any later hell, and one whose horror lay precisely in its finality.