Guardians of Ga'hoole Set [Books 4-6] the Siege, the Shattering, & the Burning

Guardians of Ga'Hoole is a fantasy book series written by Kathryn Lasky and published by Scholastic. The series, which ended in 2008 with the publication of The War of the Ember, has a total of fifteen books. Apart from the main series there are a few more books and spin offs set in the same universe. The first three books of the series was adapted into an animated 3D film Legend of the Guardians: The Owls of Ga'Hoole, directed by Zack Snyder.