From the back of the book:
Can your PC survive the mean streets of an evil city built upon the backs of the conquered? To negotiate their way safely through its labyrinthine roads, laws, and customs, your PCs had better keep their wits - and their blades - sharp!
Challenges also await adventurers beneath the city streets. Are your PCs ready for the various conspiracies, dungeons, tunnels, and creatures that lie under the City State?
Far more than just a revision, this Judges Guild classic is updated and re-imagined for v.3.5 rules. It contains a wealth of information on both the popular City State of the Invincible Overlord and on the dungeons and creatures first described in the original Wraith Overlord.