In 2077 AD, a cosmic anomaly called "Void Ripple" suddenly descended on Earth. This unpredictable energy wave will periodically sweep across the earth's surface, not only interfering with all digital signals and paralyzing electronic devices, but also distorting biological neural networks, leading to cognitive disorders, genetic mutations and other strange conditions in humans. In just three months, modern civilization, which was highly dependent on information technology, collapsed, and the global population dropped by 70%. The survivors retreated to a state of existence similar to the Middle Ages, but had to face unknown threats that far exceeded the cold weapon era.
