Many of you have checked out the various "Kos" books. There are 5 (not counting this new one) that incorporate the Swords of Kos Fantasy RPG setting. The new one is World of Kos. It's a full campaign setting book that you can use to tie all the other books together, as well as be used as a launching point into the setting for yourself and your game.
As a setting book, World of Kos covers a lot of territory... somewhat literally, as there's maps of Kos Island, the Aegean, and the Mediterranean. From there, it goes into detail about the Great Cataclysm and the ongoing war between Olympian Gods and the Titans (the primordial beings, not the American football team). This part expands into a guide to the religions of the setting. From there, get a look at the 17 races that inhabit the world. Well, that's not all the races, as there's also the monsters, which include the monstrous races. Those are described as well. The book is designed to be system-agnostic. That is, you can use it to be a part of whatever game system you feel like playing.
You can get your copy now.