In 4220 AD, Earth's civilization successfully advanced to Level Two, gaining the ability to explore between stars. Countless space fleets set out to explore and develop the surrounding star systems.
In 4500 AD, the Xuannu II Fleet made a discovery 100 light-years away in the Alpha Centauri system that stunned the entire Human Federation.
There, they found the floating corpse of a humanoid being as massive as Jupiter. After a decision by the Federation's Supreme Council, they began exploring and developing the site.
But the being's skin was as hard as a neutron star, and conventional methods could not damage it. In the end, they resorted to an antimatter bomb, finally blasting a hole in the creature's hide and obtaining a sample of its genes.
Before the fleet could study it, however, a terrifying virus carried by the corpse, which had been floating there for who knew how many billions of years, broke out.
The Xuannu II Fleet was wiped out in an instant. The virus spread at incredible speed, engulfing every star system within hundreds of light-years in just a few decades.
The powerful Human Federation, a Level Two civilization, collapsed. Some humans, animals, and plants died outright, while most mutated and became zombies.
Some animals mutated into terrifying beasts. To clear out the large gatherings of zombies and mutated creatures, the surviving humans launched nuclear strikes.
But to preserve habitable land, they switched to small conventional weapons to deal with the remaining zombies and mutated creatures. The process was extremely slow and led to terrible casualties.
Then, some powerful martial artists awakened extraordinary abilities among humanity...
