Riders of the Realm #2: Through the Untamed Sky

The second book in a thrilling fantasy adventure trilogy that SLJ called "perfect for fans of Erin Hunter's Warriors series, " from the author of the Guardian Herd series. After winning the wild Pegasus mare named Echofrost in a contest, Rahkki Stormrunner is officially a rider in the Sky Guard army. Rahkki is terrified of heights though, and Echofrost doesn't want to be tamed. But with Echofrost's herd captured by the giants and a fierce battle on the horizon, the duo will have to conquer their fears if they want to fly with the army and free the herd.
Meanwhile, back in his village, Rahkki learns of a growing rebellion to overthrow Queen Lilliam. Unfortunately, she suspects Rahkki's behind it, and she places him under intense watch. As Rahkki and Echofrost escape to Mount Crim to save Storm Herd, Rahkki worries that the greatest danger may not come from the impending battle against the giants, but from within his own clan. An Unlikely Friendship: He's a boy terrified of heights; she's a wild Pegasus who refuses to be tamed.
To save her herd, Rahkki and Echofrost must learn to fly as one. Epic Fantasy Adventure: Journey to the misty peaks of Mount Crim, face down fearsome giants, and take to the skies in a high-stakes battle to free the captured Storm Herd. Mythical Creatures: Perfect for kids who love flying horses, pegasi, and dragons, this thrilling tale is packed with adventure at every turn. Rebellion and Betrayal: As a rebellion against the cruel Queen Lilliam grows, Rahkki finds himself a suspect.
He must watch his back, because the most dangerous enemies aren't the giants, but the traitors hiding in plain sight.