Ad lit.org: Reading Discussion Guide: Freeglader by Paul Stewart and Chris Riddell

After the great battle and destruction of Undertown, its surviving inhabitants must seek out a new life in the Free Glades, but to do so will require a mass exodus across the treacherous Mire and the seductive Twilight Woods. Led by a band of surviving sky pirates, the Library Knights, and a band of protectors known as the Ghosts of Screetown, thousands of homeless seek a better life. What they don't know is that the Shryke bird creatures, the Goblins, and the evil foundry master plan to enslave them. It's up to Rook, Felix, Xanth, and the others to fight for their very survival as Freegladers.