Book Four of the Codex Alera. After two years of bitter conflict with the hordes of invading Canim, Tavi of Calderon, now Captain of the First Aleran Legion, realizes that a peril far greater than the Canim exists-the terrifying Vord, who drove the savage Canim from their homeland. Now, Tavi must find a way to overcome the centuries-old animosities between Aleran and Cane if an alliance is to be forged against their mutual enemy. And he must lead his legion in defiance of the law, against friend and foe-before the hammerstroke of the Vord descends on them all.