I've probably read two dozen books in the last year, and Lev Grossman's The Magicians was my favorite. (Indeed, the next time I have the opportunity to commission art, I might ask for a drawing of the book's villain.) Here's the cover to the sequel, The Magician King, which is available for preorder at Amazon.
The image is actually a photograph of a model by Didier Massard. You can read an interview with him here.