Stage Four beings were far more powerful than Stage Three existences.
There existed a fissure between these two stages, and it wasn't easily crossable.
In this apocalyptic world were countless creatures below Stage Four.
Due to the changes in the world's order, the human race forcefully reversed their way of living to adapt to the new order—where the strong survived, and the weak died.
Rather than saying that this was an apocalyptic world, it was more like an apocalyptic game.
In this game, everyone was split into different levels. Stage One to Three existences were like players who had just entered the game and were starting to learn about the game. A lot of humans and other creatures were at this stage.
They increased their strength by leveling up. They surpassed a normal human's limits, gaining strength that allowed them to shatter boulders and break mountains.
