Horus accounts have the penis of Osiris surviving). After becoming pregnant with Horus, Isis fled to the Nile Delta marshlands to hide from her brother Set, who jealously killed Osiris and who she knew would want to kill their son. There Isis bore a divine son, Horus. Since Horus was said to be the sky, he was considered to also contain the sun and moon. It became said that the sun was his right eye and the moon his left, and that they traversed the sky when he, a falcon, flew across it. Later, the reason that the moon was not
The Horus Heresy (novels) Heresy and "Warhammer 40,000" canons; still other non-series Horus Heresy material has been eventually incorporated into the work. A significant development was the 2012 initial release of the "Horus Heresy" miniatures wargame expansion, which repositioned the concept as a foreground element within the "Warhammer 40,000" gaming system while highlighting the importance of the Horus Heresy to Games Workshop's product lineup and the related universe. The expansion is reputedly developed in coordination with the book series, and includes new material and information about the Horus Heresy and the fictional universe; it joins the series and other works as an authoritative source