The Skeleton Warriors are using human slaves in factories to make bombs used to capture more slaves and soon on Luminicity. Planning to break in and see what's being built, Ursak creates a weapon that will break a Skeleton Warrior's heartstone, returning it to a human. To stop the work and the killing of rebels, the Legion of Light frees a group of resistance fighters then has Urssak enter the factory disguised as a worker. He gains the Skeleton Warrior's trust by fixing a few things, but the workers who sabotaged them think he's sided with them so aren't ready to listen to his plan to help them escape. Then he's captured before he can finish.