Inkworld: The Color of Revenge (the Inkheart Series, Book #4)

"Five years after the events of Inkdeath, Meggie, Mo, and the people of Ombra lead peaceful lives, their fires warmed by the flames of Dustfinger--the Fire-Dancer. But when Dustfinger spots Orpheus's glass man within the gates of Ombra, a familiar restlessness begins to haunt him once more. And for good reason. The past five years have been a different story for Orpheus, who has spent his days living a meager and deprived existence, fueled only by his thirst for revenge against Dustfinger and all those who betrayed him. Now, Orpheus has found an unexpected way to seek vengeance against his greatest adversary. He has corrupted an artist to create bewitched portraits that will see the heroes fade to gray"--