The battle for the Mud Whale has become a deadly rout as the Marked fight to protect their home and their comrades from the invading apatheia soldiers. Meanwhile, Chakuro and the rest of the boarding party have made it safely onto the imperial battleship Skyros, but their mission turns bloody when they reach the thymia-shielded chamber at the heart of the ship. How will they destroy the enemy Nous and save the Mud Whale without access to their power?