From your Wall Street Journal bestselling author of The Paper Magician Series comes the enthralling climax of the cataclysmic war between monstrous creatures.

Sandis has finally freed herself from her get good at and his programs to make use of her being a vessel for the ancient beast Kolosos. But her get good at has found a new, impossible vessel: Sandis’s sibling, Anon—a sibling she long thought dead.

Kolosos is ancient, massive, and seemingly unbeatable. Fortunately, Sandis provides her own monster—an ethereal fire equine about Siege and Sacrifice that she can summon at will. Furthermore, she and Rone may can see the secret to defeating Kolosos: historic lore that information the creation of magic. It could be the main element to victory and the main element to saving Anon.

The price is steep, and Sandis is ready to pay it. Rone is not, and his attempt to save her only pulls them aside. As both are examined in ways they never expected, Sandis and Rone should determine the sacrifices they are willing to make. If their efforts are not enough, their town will fall…just as the ancient city beneath it currently has.