In 20XX AD, human beings were suddenly attacked by demons. Most of the countries were destroyed in just two or three years, and a large number of people were killed by monsters. Only a few countries were unable to regain their land and could only use the remaining population Concentrated in a few limited cities. After several years of fighting against the demons, the remaining humans have developed a chip that can stimulate human potential and enable humans to gain powerful combat power. However, the energy of the chip is too powerful and only a few Some people can be completely matched successfully, and those who successfully match with the chip are both brave men, carefully cultivated by the remaining humans, and shoulder the important task of fighting against the demons and saving mankind. The male protagonist is one of them. He will learn various Battle knowledge, and fight together with elites from all over the world to save this collapsing world.