Out of all the big fantasy game franchises, what's the best book.

Out of all those fantasy franchises based on games (Dungeons and Dragons, Warhammer, World of Warcraft, etc) that pump out like hundreds of books, are there any works that stand above the rest. Although I'm not too familiar, heard some people describe books from theses franchises as "junk food fantasy". Have any books come out of these franchises that could be considered like peak literature.