Slumbering Tsar: The Hidden Citadel, Part 2: Echoes of Despair

From the publisher's website: The player characters continue to plumb the true depths and echoing halls that are the Citadel of Orcus. Within they explore the Templar Garrison and Dungeons of Orcus and discover their profane occupant, remaining after all these years. They discover the Thrall Quarters and the Forges and the lingering horrors of the Magitect and the legacy of He Who Walks Before.