On the hive world of Absalom, god-machines go to war: loyalist Titans under the banner of the Fabricator General of Terra clash against the forces of Horus Lupercal, Warmaster and arch-traitor. By the time the Emperor-class Titans of the Legio Castigatra arrive, the Legio Audax, also known as the Ember Wolves, have long been lying in wait for their prey. When a traitor Warhound pack spots the loyalist Titan Tantorus Magnificat striding through the ruins, they know they have found a target worthy of their battle-pack, and eagerly launch their attack. Though their hunt is successful, when the Warhound princeps gather round their downed prey, they discover that their fight is not yet over. Read it because Titans battle Titans in the midst of the Horus Heresy, but nothing is quite as it seems when the Ember Wolves strike.