This is a world after nuclear peace. Humanity is divided into two camps. People who successfully withstood nuclear radiation by reproducing on the surface developed mutants whose bodies mutated. Relying on the technology left before the end of the world, you can avoid radiation and survive down there. The animals and plants on the surface have also mutated. The originally towering cities have disappeared and become a world of mutant beasts. Humanity's survival is at stake, and mechas emerge as the times require. On the one hand, it is used to resist the intrusion of mutant beasts, on the other hand, it has also become a weapon in the war between the above and underground. Can mankind survive in this apocalyptic world? Can we return to the way we once again ruled the world before the end of the world?
