Oathbound: Domains of the Forge is the core book of a d20 system campaign setting designed to either stand alone or serve as a "capstone" or temporary side-campaign within an established campaign. The premise is a world ruled by seven powerful angelic beings (the "Feathered Fowl") who are bound by oath to guard an imprisoned god forever — unless they are defeated by a being of even greater power. To gain their freedom, they continually pull beings from across the planes to their domains, which are effectively huge crucibles designed to forge a being who will be able to defeat them, and thus set them free.
From the back cover:
They are the four-horned Feathered Fowl, once great champions of a god lost to memory. Now, they have been turned against him and bound to serve as jailors of a divine prison. Straining against the confines of their Oaths, they scour the multiverse seeking the 'greatest of the grand', ripping them from their homes and bringing them to the Forge.
Domains of the Forge
The divine power of the trapped god seeps into the land and its heroes, imbuing them with great powers and abilities. Unique prestige classes give insight into the world's mysteries and allow heroes to thrive within its borders, leaving them forever changed.
A countless wealth of races, cultures, magic, and knowledge has been pulled to the land from millions of other worlds, woven into a unique tapestry that is the Forge. You will be forever altered.
This product is a supplement for the Dungeons & Dragons core rulebooks. It is published under the Open Gaming License (OGL) and is compatible with the D&D 3.0/3.5 edition rules and the D20 System.