Robert Silverberg 
King of Dreams [EPUB ebook] 

The years since first he gained the Starburst Crown have been difficult ones for Coronal Lord Prestimion and the vast, unfathomable realm he rules. But finally peace has been restored to Majipoor. And now it is time for Prestimion to name the able Prince Dekkeret as his succeeding Coronal and to descend to the Labyrinth as Pontifex. But a power from a dark past that both men believed was dead is stirring once again — an evil more potent and devastating than either leader dares to remember.