In 2020, the anti-cancer drug "Crypto No. 1" Was born, and Mill Pharmaceuticals became the world's number one pharmaceutical company.
In 2023, patients who took the "Code" series of drugs began to experience strong side effects. The human body mutated, appeared "living dead" characteristics, and gradually became "zombie", and spread through saliva and blood. Countries have stepped up defense and isolation measures, and national armies are fighting against mutated zombies.
In 2024, zombie mutations are gradually developing in a serious and dehumanized direction.
At the end of 2024, state power in various countries gradually collapsed.
In 2025, the last country was officially destroyed. At this point, human civilization fell apart, and the people spontaneously formed a reserve to fight against the zombies.
In 2026, the "Black Hawk" organization appeared, claiming to master zombie control technology, and announced that it would use zombies to "rebuild the world."