In Egyptian mythology, the mythological being that guards the entrance to the underworld is Anubis. He is depicted as a man with the head of a jackal and is recognized as the god of mummification and the protector of the deceased. Anubis plays a vital role in the judgment of souls, overseeing the weighing of the heart against the feather of Maat, the goddess of truth. His presence ensures that the journey to the afterlife remains just and fair, acting as a guide for souls into the realm of the dead, where they face their deeds in life.