Upon the flight of the queen
(Book)

"While the savage Naor clans prepare to march on the heart of the Five Realms, Rylin Corimel infiltrates the highest of the enemy ranks to learn their secrets and free hundreds of doomed prisoners. His ailing mentor Varama leads the Altenerai corps in a series of strikes to cripple the Naor. Kyrkenall, Elenai, and the kobalin Ortok ride for the storm-wracked shifting lands to rekindle the alliance with the winged lizards known as ko'aye, the only possible counter to the terrible Naor dragons. Meanwhile, the queen is delving further and deeper into the magic of the mysterious hearthstones, in a frantic attempt to save the realms that just might doom them all."--,Adapted from publisher.