One hundred and thirty years of the Ash Era. A huge wall stands up to divide the pure land and the wasteland. Shen Lian was once the sharpest knife within the wall, and was affiliated with the "Dust Purifier". His duty was to clean up all unstable factors outside the wall, including compatriots who were out of control. During a routine decontamination mission, he refused to pull the trigger on a "Rust Slough" infected person who had shown signs of human resurgence. The price is exile. The "spine" of the military-grade symbiote implanted in the body was forcibly locked, and his left arm was replaced with an old civilian prosthetic "Rust Bone". He was thrown out of the giant wall like garbage.
Outside the wall are radiation, mutated beasts, resource plunderers and scattered survivors struggling in despair. Shen Lian, who had lost his power, struggled to survive until he found a dusty fragment of the "Dawn Theory" deep in an abandoned laboratory. It recorded that "rust slough" was not a curse, but another evolutionary possibility that humans were forced to open under radiation. What the Purifiers have been purifying for hundreds of years is the fire of evolution.
At the same time, a new pursuer was sent inside the wall, vowing to eliminate him as a traitor and the secrets he discovered. Shen Lian clenched his rusty left arm and looked at the huge wall towering into the clouds. Perhaps, true purification and salvation never lie within walls.
