Once upon a time, Guardians of Order arose to protect the roleplaying landscape against the forces of Chaotic Market. Guardians of Order fought valiantly, but in the end, the relentless energy of Chaotic Market slew them. Like fallen armor and weapons of a valiant hero, pieces of Guardians of Order were picked up by others in an attempt to continue the battle. A token fell from the sky. The rights to Uresia: Grave of Heaven fell back to their creator. Years have slowly crept by. Uresia has returned.
Imagine a fantasy world where the Gods fought long and hard enough to kill themselves; where the heavens literally fell to the world below; reshaping the surface of the world. A broken ring of islands is all that seems to remain. Remnant magic drew survivors. The ring of islands outside left to the trolls.
Uresia: Grave of Heaven is that fantasy world. The book is part of Cumberland Games and Diversions All-Systems Library. No specific roleplaying system is implied or required (although fans of Risus can use the Risus-ified version of those rules: Uresius: Grave of Anything). A quick note: while there is nary a mention of any RPG in the book, the book does provide rules for a Uresian board game called Mastery.
This 114-page PDF (also available in dead tree format) provides you a synopsis of 16 of the larger island-nations (about 30 full pages of details and information to whet your appetite for more). You are also provided with a nice hamlet-sized morsel called Rogan’s Heath with enough details to feel that you actually know the residents of this nice little place. You are also given an amazing view into Shadow River, a bustling city with enough districts and uniqueness to keep your players intrigued for quite some time. You also get a quick glimpse into more traditional roleplaying elements in the Beneath and Beyond section (dungeons, ruins, and the like).
Once you are introduced to the world and some of it’s inhabitants, you get into more traditional roleplaying elements. You are provided a variety of character races to use as examples: Beastmen (Hramath), Wise Beasts, Centaurs, Dwarves, Elves, Demons, Humans, Mushroom Trolls (the Mourfa), Snowmen, Slimes, Satyrs, and Troll-Landers. You are given some notes on how to flavor magic for different styles presented in the world section, the scale of the world, and a fully realized section for how to price things in Uresia (and how to use that to your advantage when applying it to your RPG engine of choice).
There is one table in the game that you can roll against, and it is a lot of fun: the Big Table of Life-Altering Moments. Simple rolls 3-5 d1000s (i.e. 3, 10-sided die) and make note of the resulting rolls. Look them up on the table and make up your background story to fit the results. While the table will give you seemingly generic results, you can have a lot of fun applying things like “You found out how liberating a great disguise can be” to your character’s background story.
A word on scale: Uresia is a pretty big place. The islands roughly take up the same area on a map as the US (or, as the text describes: Uresia, combined, is the same overall size as Western Europe (twice that if you include the Troll Lands)).
So, the book provides you with enough details to have fun with most of the major islands (from a geo-political stance at 16). There are thousands of islands. This equals the perfect opportunity to expand upon Uresia and add islands of your own design. Anything can be possible in a world where the heavens have crashed into the world. You could easily add something from your current campaign as a nation in Uresia, and the rest of the world wouldn’t even blink.
I think that is the shining thing in Uresia. You are given enough to have fun with it as is, but you can tweak to your heart’s content too. You can easily make it your own (and you can use whatever RPG system you like to play in it). It is definitely one of the best world books I have read in a very long time (and is gorgeously laid out as well).