I Have a System That Leads to Longevity

"Survival in the apocalypse, dark underbelly, novel themes, rebirth, no system, no harem, and the plot is not boring" is recommended to start reading from the second volume. . Due to the changes in the planet, human civilization welcomes selves in each plane. Do they have the courage to kill themselves and survive in place of each selves in the plane? The sudden mutation of the Blue Star caused great turmoil on the planet and the emergence of dimensional space. A large number of mutated creatures rushed out. Humanity is facing the biggest crisis in history. Should we stay together to stay warm, or should we fight separately? For people who want to live... Become stronger, due to the distortion of human nature and the loss of morality, everyone is a god of death. In order to increase the level and usher in a stronger self, whether to use a knife to kill mutated creatures and slowly level up, or to kill all of one's own kind to quickly obtain crystal cores to increase the level... Weak and helpless people! The killing begins... The introduction is weak, so move on to the main text.