osiris4dOverview. Osiris, the Mhty One, was both god of the dead and a central fure of Egyptian mythology.His cult arose around 2600BCE, as those of competing deities,The family of Osiris, the protagonists of the Osiris myth. Osiris is depicted on a lapis lazuli pillar in the center, flanked by Horus on the left and Isis on the rht in this Twenty-second Dynasty