Vincalis the Agitator

A prequel to The Secret Texts trilogy set 1,000 years earlier. From the back cover of the Warner first edition: "Glory of the dragons - Based on a science of sorcery called Dragon magic, the Hars Ticlarim is a miraculous place of mansions built on clouds and gardens blooming diamonds beneath canopies of captive stars. But this incomparable beauty hides a dark core: Dragon magic draws its power from the agony of slaves who are killed for sorcerous fuel. And for three thousand years, no one has dared question the empire's inhuman cruelty... until now. Wraith, a boy with an uncanny power, seeks the art to foment a revolution within the Hars Ticlarim. Solander, a brilliant young mage, believes he has discovered a totally new form of magic. Luercas, a sadistic noble, will commit any crime that furthers his ambition. All three are clever, resolute, driven - and naive. For they challenge the rulers of a globe-spanning power that has endured for millennia - rulers who will do anything to stay in power forever..."