The Siege of Macindaw (Ranger's Apprentice, #6) [Paperback] John Flanagan

In this desolate northern fief, where can Will find the fighting men he needs to overcome the traitorous Sir Keren and his band of criminals? Across the border, the fierce Scotti tribesmen are waiting for the signal that Castle Macindaw is in friendly hands, and the way is clear to mount a full-scale attack.