After a week of experiments, it was found that the potion provided by Xie An could indeed solve the current nuclear pollution problem. However, some components of the potion were developed in their era. We could only rely on them to produce a large quantity and send it over through the system because their population was relatively small, so the process would be slower. The materials needed for the antidote to treat the zombie virus were available in this era. After scientists obtained the formula, they started extensive research and administered it to all survivors through injections. Those humans who turned into zombies were already dead. Even if the antidote could eliminate the zombie virus for them, they couldn't come back to life. However, marine organisms were different. They didn't carry the zombie virus, so they could recover and return to normal. The first area to be purified was the most heavily polluted sea area, and after three days, it had returned to its previous state. According to the weather forecast, a typhoon was expected to arrive in three days. The experts planned to release the purification potion for nuclear wastewater and the antidote for radiation into the ocean before the typhoon arrived. Through ocean currents, the potions would reach farther locations, accelerating the purification process. One year later, all sea areas were fully purified, and the damage caused by nuclear radiation to marine organisms had completely disappeared. As for the country that discharged nuclear wastewater, it faced nature's revenge. On the second day after purification, a massive earthquake occurred, triggering a tsunami. The flooding was severe, and within a month, that country became a ruin. Survivors were evacuated to safe places. Thus, the doomsday officially ended, and humanity returned to the days before nuclear wastewater was discharged into the sea. Xie An said that this would be their final attempt to bind with us. If they failed again, humanity would be completely wiped out. Luckily, they succeeded. Later, Xie An mentioned that besides me being his ancestor, the selection of other hosts was also deliberate. For example, Wen Ye's father was a billionaire with extensive connections. The development of the potion required financial support, and only by participating in this mission would his father believe that there truly was a system in the world and that someone could solve the nuclear wastewater problem. Ye Man's father held a high-ranking position, which carried significant weight. He could make the final decision on whether to use the potions. Chen Jiang's uncle was a scientist who could provide evidence with his knowledge and understand what we were talking about. The selection of other hosts followed a similar pattern, all for the purpose of ending the doomsday and saving humanity. I couldn't receive the money rewarded for completing the missions. It was just a pretense to persuade me to undertake the tasks. Another year passed, and I returned to the university campus, resuming a routine life of classrooms, cafeterias, libraries, and dormitories. The doomsday ended completely, and the trajectory of Xie An and the others changed. I had no way to contact them anymore. They said that even if they ceased to exist in the future, as long as humanity could live well on Earth, their sacrifices would be worthwhile. Three years later, Wen Ye and I got married and had an adorable daughter named Wen Nian Man. (The End)