On July 20, 2030, an electromagnetic storm appeared in the sky, and an unknown virus descended. At two in the afternoon, dark clouds covered the land. Lightning flashed and thunder roared, and most of the world's electronic systems were damaged and stopped working. Satellites, networks, artificial intelligence, and everything else became unusable.
Most of humanity was infected by the virus and turned into zombies. Only a tiny fraction survived, struggling to stay alive. Both humans and zombies began to evolve. The battle for survival had begun.
In later generations, people named the virus Heaven's Punishment. It symbolized the idea that humanity's destruction of nature had become so appalling that Heaven could no longer stand by, and had sent this disaster as divine punishment.
