Gou's Liver Experience Upgrade in the Post-Catastrophic Era

Some people say that this is an invasion by advanced alien civilization, but no one can provide evidence. In 2226 AD, all living things on the earth mutated overnight. Animals turned into powerful blood corpses and evolved various weapons and abilities. Plants purified their digestive systems and attack systems. Even microorganisms were no longer ordinary and became dangerous. What is even more chilling is that the main food of these creatures has all become humans. The original planet overlord has become the bottom of the food chain overnight. After the final nuclear bomb war failed, humans built mobile cities one after another and escaped from the ground. Luo Xiu has never left Mobile City since he was born. His daily task is to work continuously to earn the qualifications to continue to stay in Mobile City. There is something strange in his mind that allows him to continuously accumulate experience and upgrade various skills. At first he just wanted to be a genetic warrior and go to the ground to see, but he didn't expect that one day he would become a savior.