Jack of Shadows
First review from amazon
In this novel, Zelazny takes on a number of themes and situations and subverts them all through an allusive, elliptical style that allows multiple interpretations. The title character is a man who is constantly between extremes - he's the master of shadow, in itself an intermediary between light (which in this book governs the world's `scientific half') and darkness (which governs the `magical half'). All the dichotomies Zelazny juggles with - light and darkness, science and magic, good and evil, etc. - are always part of the same whole, and the fact that both parts are usually seen as mutually exclusive fuels many of this book's episodes and produces some tension. Throughout the novel, hints are scattered about Jack's double life as a magus and semi-god in the darkness, and as a teacher in the light; meanwhile, Jack faces adversaries representative of light (elaborate machines) and of darkness (strange creatures), and he uses both technological knowledge and magical incantations during his quest. The book is another kind of initiatory voyage, since Jack has been there before but still must go through several challenges, and in the toughest of them he is often confronted with himself - either when put in a chamber of mirrors or when discussing with his own soul. His quest is ultimately a complex quest of self-discovery.
Second review from amazon
A truly unique world, as complete as Tolkien's Middle Earth in a long short story. I read this when it first was published in two parts in a sci-fi magazine and was delighted when it came out in book form. Shadow Jack, the thief, is beheaded at the games for eying the HellsFlame, the bride price for Evene of the Castle Holding. He awakes naked and whole in the Dung Pits of Glye, as all dark-siders do, and must make his was back and avoid his arch-enemy, The Lord of the Bats. What a ride! He conquers the world, then destroys it and himself. Or does he? The Arts, the vampire rock, and MorningStar chained at Everdawn, a half-world of light, reason, and technology, a half-world of darkness, magic, and myth. I can't recommend it highly enough.
more informations here:
http://en.wikipedia.org/wiki/Jack_of_Shadows
*Btw: Some pictures will be added soon