Knot Gneiss
"When Wenda Woodwife is suddenly overwhelmed by maddening mood swings that drive away her beloved Prince Charming, she beseeches the Good Magician Humfrey for a cure for her condition. But instead, he asks her to undertake a daunting and thorny mission that only she might accomplish. For an ancient Knot of petrified reverse wood has become malicious and menacing, radiating fear and chaos across the land of Xanth. With a loyal band of stalwart companions, including a curvaceous winged mermaid, a beautiful fallen angel, and a handsome lovelorn prince, Wenda sets out to confront the peril, only to find herself thwarted by a host of hostile adversaries, including a seaweed sea serpent, devious Demons, and even bug-eyed monsters from an alien world!" -- Back cover.