From publisher blurb:
Deep beneath the ground, in those regions where the echoes of mankind’s feet are seldom heard, where even firelight is a bizarre intruder from a long-forgotten place, the foes of mankind breed and multiply. It is a realm of dark chaos – for these creatures of the echoing deeps count each other as rivals and enemies. It is a place without peace, a place without virtues, a place where every countenance of evil is to be found in sluggish torpor, stirring restlessly in dreams of cruelty and hatred. These dark and deadly provinces are known as the Under Realms.
Most named regions in the Under Realms are quite distinct from each other, whether by geological formation or by the types of inhabitants that have established themselves in strategically important areas. Characters who enter this area expecting to find drowic elves, deep gnomes, and other “normal” features of the Under Realms will swiftly discover the error of their thinking. The Vaults of the Sunless Sea, located to the north of the Cyclopean Deeps, might fit that description, but the Cyclopean Deeps are a different and decidedly more unpleasant area into which the denizens of the Vaults seldom venture.
This series of adventures forms a mini-campaign in the depths of the earth, suitable for a party of 4+ characters with an average level of 10-12, or 8+ characters with an average level around 7.
CD1: Down to Ques Querax
The first adventure in the Cyclopean Deeps mini-campaign, Down to Ques Querax introduces the perils of the Under Realms with encounter tables, region map, and many new monsters. Designed as the "link" to Rappan Athuk, this module may also be used to connect any deep dungeon to the Under Realm.
CD2: Eye of the Titan
The second adventure in the Cyclopean Deeps series by award-winning author Matt Finch. Eye of the Titan takes the adventurers to the strange, underground fortress of Ques Querax, where they may discover strange secrets if they are unlucky enough...
CD3: Izamne, City of Endless Dark
The third installment of the Cyclopean Deeps describes Izamne, the city of the dark stalkers, a huge basin-cavern where thousands of denizens of the Under Realm trade, murder, and scheme in the total darkness of the "Law of Last Light." This installment is best used together with Cyclopean Deeps 4: Secrets of the Dark City, in which more about Izamne is revealed. Contains 2-page player map and 2-page Referee map.
CD4: Secrets of the Dark City
The fourth installment of the Cyclopean Deeps, Secrets of the Dark City will be the second half of the book's third chapter, which covers the vast underground city of the dark ones. The dark stalkers and their mysterious servants the dark creepers are by no means the only perils of the great, open-caverned city -- the plans of a thousand villains crisscross in the dark places of the world.