Synopsis:
In 2111, a gigantic portal suddenly appeared in the world, and countless monsters poured out. They were immune to most conventional weapons, turning the world into a living hell. Some people thought that if there was no way to deal with the monsters here, perhaps there might be one beyond the portal. And so, people began venturing through it.
Then someone emerged from the other side, having killed countless monsters. More and more people followed in their footsteps, only to discover that the monsters pouring through were the weakest of all. Even stronger ones gradually began appearing in the world.
More than ten years passed before someone brought back a stone tablet containing countless battle spirits. These spirits could teach people martial arts and combat techniques, as well as possess them and greatly enhance their fighting power. The monsters in the world were gradually eliminated, leaving only scattered outbreaks. Though many still died, people were at least given a brief respite.
At the same time, large numbers of people entered the portal and discovered that as long as a certain number went through each year, the monsters could only emerge from the other side. The more people entered, the weaker the monsters that came out. And so, evil took root. From then on, people began calling the other side of the portal the Abyss.
