In the new era of the earth more than 10,000 years later, monsters roam freely. Although human beings have finally been able to fight against them after years of exploration. However, the end of the world has not yet ended... A magic gun in the underground world has changed the original useless life. Young Yang Yongyi, with a gun in hand, the world is no longer empty talk. But Yang Yongyi's goal is to end the end of the world! Let's see how this magic gun and a young man write their own stories in the end of the world...