Jackal-headed Anubis holds the ultimate judgement over the dead, measuring every heart against the weight of Truth.
Nephthys, wife of Set - the God of Darkness, desired a child, yet her husband was infertile, so Nephthys disguised herself as Isis, the wife of Set's brother Osiris, and seduced him. From that union, Anubis was born. Osiris cared for Anubis as his own, but when Osiris was murdered by his evil brother, Set, Anubis embalmed his adopted father and mummified the corpse so he would not rot. This preservation passed down to the Faithful, for it was good enough for the Gods, it was good enough for man.
None enter the abyss of the Underworld without first being tested by Anubis. When corpses are preserved, he is the embalmer. When time for judgement comes, he is the final arbiter. In his realm, he keeps legendary weighing scales. On one side, the massive weight of Ma'at - truth and order. On the other side, he places the heart of the deceased. Should the weight of Ma'at prove infinitely heavier than that of the heart, Anubis casts the soul deep into the darkness of the Underworld, where it is forgotten, never to be reborn.