Before the cataclysm, the number of people on Earth was about the same as it actually was, in the billions. However, the cataclysm has led to an unprecedented crisis for humanity, and the surface world has become uninhabitable. The humans who are currently participating in and about to participate in the game are all people who have been transferred to the shelter in time, making up only a small percentage of the total population of the world, similar to the survivors of Noah's Ark, who on the one hand prolong their lives through hibernation devices and wait for the surface world to return to its original state, and on the other hand, they also send pre-set robots to help clean up the surface world, while all the rest die in the disaster. So at this moment, the rest of the world's population, which is also the total number of "second world" players and future players, is less than 6 million.