-- Gene Wolfe's science fiction is acclaimed for literary excellence. -- Cover by award-winning science fiction and fantasy artist Don Maitz. -- Includes maps and a comprehensive glossary of the "New Sun" background...a valuable resource for any Wolfe fan, gamer or not
I'm not entirely sold on the idea that this works as a setting for an RPG, but I will say this: There's a seven page summary of the New Sun series, going through event-by-event, and reading it made so many things clear that I didn't get from actually reading the books. It almost makes me want to go back and read them again with an actual understanding of what's going on.
I know literally nothing about GURPS or D&D in general (though it does seem interesting?), and so I'm not sure how well this book works as an actual D&D thing, but for fans of New Sun this book is almost as useful as Andre-Driussi's Lexicon Urthus, and is actually an improvement over that text in some ways (the maps and histories are incredibly helpful.