Books with title Attack of the Sky Pirates

Rook Barkwater lives in the network of sewer-chambers beneath Undertown, the bustling main city of the Edgeworld. He dreams of becoming a librarian knight - one of those sent out to explore the mysteries of their world. Somewhere out there lie the secrets of the past - including the lost floating city of Sanctaphrax - and, maybe, hope for a future free from the fear of tyranny. When his chance comes, Rook grabs it! Breaking all the rules, he sets out on a journey to the Free Glades and beyond. His luck and determination lead him from one peril to another until, buried in the heart of the Deepwoods, Rook encounters a mysterious character - the last sky pirate - and is thrust into a bold adventure that dares to challenge the might of the dread Guardians of the Night...

The first book of the Rook Saga, part of the bestselling Edge Chronicles series. Far out in open sky, a storm is brewing. In its path is Sanctaphrax -- a city built on a floating rock and tethered to the land by a massive chain. Only Twig -- a young sky pirate captain who has dared to sail over the Edge -- has learned of the approaching danger. But his perilous voyage destroys his sky ship, hurling his crew into and beyond the Deepwoods, and robbing Twig of his memories.