The Behemoths are changing. Their blood moves long after they die, and someone is shaping them. Arctus, a mage who left his Tower to hunt the source, joins forces with Lucian, a thief driven by grief, and Fen, the warrior known as the Crimson Devil. As they follow the black blood across a broken continent, they discover that the monsters may be the lesser evil, and that every victory they win comes at a cost.