Redwall by Brian Jacques
When the peaceful life of ancient Redwall Abbey is shattered by the arrival of the evil rat Cluny and his villainous hordes, Matthias, a young mouse, determines to find the legendary sword of Martin the Warrior which, he is convinced, will help Redwall's inhabitants destroy the enemy.
The Guardians of Ga'Hoole: The Capture by Kathryn Lasky
When Soren is pushed from his family's nest by his older brother, he is rescued from certain death on the forest floor by agents from a mysterious school for orphaned owls, St. Aggie's. When Soren arrives at St. Aggie's, he suspects there is more to the school than meets the eye. He and his new friend, the clever and scrappy Gylfie, find out that St. Aggie's is actually a training camp where the school's leader can groom young owls to help achieve her goal.
When eleven-year-old Gregor and his two-year-old sister are pulled into a strange underground world, they trigger an epic battle involving men, bats, rats, cockroaches, and spiders while on a quest foretold by ancient prophecy.
Eleven years after the cruel Killdeer took over the Catacombs far beneath the human's Trillium City, Juniper Belancourt, assisted by Vincent and Victor Nightshade, leads a maverick band of rats to escape and establish their own city.