Maske: Thaery by Jack Vance

Used; Hardcover - Good; 1976 1st edition; wear on the dust jacket; page edges have discoloration. 

On Maske, one of twin planets that orbit around the lost star of Mora, the Droads, a clan of warlike dreamers rule, and with his brother Trewe destined to become ruler, second son Jubal Droad sets his sights on pursuing a life of adventure