Red mist shrouds the world, mutating each day with the “Metallic Tide” and causing a disease that turns people to metal. The floating bases are rigidly hierarchical, resources are unfairly distributed, and iron-shell monsters continue to evolve. As Lin Ye searches for his younger sister, he exposes the Iron Guard’s lies and investigates the truth behind the “Purification Project.” Caught between the choice to exterminate or coexist, he sets out on a path toward coexistence between humanity, the red mist, and the iron-shell monsters.