The Sky Pharaoh Hakotep I has risen and launched an attack against the city of Wati with his infamous flying pyramid. The heroes return to Wati to defend the city against this menace, only to discover that the attack is just the preface to a larger invasion of Osirion, controlled from Hakotep's own flying tomb. Will the heroes call down the flying pyramid of the Sky Pharaoh from the sky, or will their bones join the thousands of skeletons that lie within the slave trenches of Hakotep? A 13th-level Pathfinder adventure, The Slave Trenches of Hakotep continues the Mummy's Mask Adventure Path.