Vale of the Vole (Xanth Book 10)
Crewel Lye (Xanth Book 8)
Dragon on a Pedestal (Xanth Book 7)
Heaven Cent (Xanth Book 11)
Night Mare (Xanth Book 6)
Ogre, Ogre (Xanth Book 5)
Centaur Aisle (Xanth Book 4)