No, Xanth is a fantasy world, and the books are comedic, and filled with silly puns, but are good adventure, as well.
This is what you're thinking about: http://www.amazon.com/Necroscope-Brian-Lumley/dp/0765320185/ref=sr_1_3/185-4091114-3840636?ie=UTF8&qid=1432915677&sr=8-3&keywords=necroscope