Is human existence on earth really absolute? In the 31st century, the earth's environment began to deteriorate: food, water, and even the air we breathed were found to contain excessive amounts of poison. Immediately afterwards, a type of acid rain called HK700 covered the entire earth. This kind of acid rain is highly toxic and corrosive. The strong acid rain caused the biological cells on the earth to begin to mutate. At first, there were only cats, rats, and dogs, but then, mutant people appeared. Due to the mutation of cells, the human body structure underwent horrific changes... In an accident, Arnold unfortunately encountered acid rain and mutated, and then a series of misfortunes - cannibalism, human experiments... He was tortured, and almost desperate, he was accidentally rescued by a mutant swordsman. After some teachings from the swordsman, Arnold regained his confidence in living, and gradually began to accept the life of a mutant. Unfortunately, the swordsman died in order to protect Arno. Arno, who was heartbroken, joined the Xuementang, an organization of aliens, and trained in the Xuementang... This is the annihilation of human nature. The aliens are the shadow of human beings under the powerful light of technology. Are alien species dominating humans? Or are humans dominating alien species? Can humans allow the existence of creatures that are truly equal to humans? Which side is right? Everything will be revealed soon...