Slumbering Tsar: The Temple-City of Orcus, Part V: Foundations of Infamy

From the publisher's website: The secrets of the city have been laid bare as brave heroes reach its pinnacles only to discover they have only scratched the surface of the dread they face. For after braving all the perils they have, PCs discover that the Foundations of Infamy merely provide the means of reaching the final challenge—The Hidden Citadel. This adventure explores the upper reaches of the city known as the High Terrace, the Maze, the Darken Bridge and the Plateau of the Demon Prince.