The bulk of the campaign book are descriptions of the Provinces by chapter. Listing the major city, history, adventure hooks, NPCs, and so forth — Campaign Details.
The campaign guide will also include the adventure "Rogues in Remballo", which will be going out free to backers tomorrow (Saturday Oct. 16). Don't worry, though, we will be linking the free module to the general public from our KS page for everyone else the next day.
No new spells, classes, or archetypes. This book really focuses on the lands that have just been mentioned in our other products in the area (Chiefly Rappan Athuk, The Lost City of Barakus, and Sundered Kingdoms).
What it ISN'T is just a list of NPC stats. It's a sandbox campaign setting that you can build off of, use with our other Lost Lands products, or outright steal content from for your home game!