A new world created by a bored God.
A world where strength rules and every species fight for survival. Before entering the Abyss, species are each put in a separate buffer zone, The Otherworld, where they learn to adapt to the Abyss. The more knowledge about the Abyss is spread among the species, the faster the descent of the Abyss will be which will in turn cause the time in the Otherworld to shorten.
In the Abyss, people will start off on the first floor and can go down to deeper floors (similar to going down floors in a dungeon). The first floor is the least dangerous and it gets more and more dangerous the further down the Abyss you go. It is suspected that it is called the Abyss because you could go down forever (there is no end). In Hansoo's previous incarnation, he had already gone down very deep into the Abyss, much further than Elkadion, until he met dragons and other extremely strong creatures of the Abyss.
The Abyss has an extremely harsh environment in which one would need to protect themselves by using skills. It is as harsh as a sea of lava. There are places where meteors fell and places where lightning struck down every time one took a step. Some places don't have any air and others have gravity several tens of time stronger than normal. In the first timeline, everyone below the Violet Zone were killed when the Abyss occurred.
When the Abyss opens, the Great Collapse will occur. A tremendous tremor that everybody could feel will ring throughout the entire world. The sky will break apart. The clouds will split as a crack appears. The grounds will shatter. Mountain ranges will break down as fissures appeared. Holes will appear in the skies and in the earth and continue to enlarge until they stabilized. Huge metal pillars will descend from the sky and land upon them. Light will appear on the metal pillars. Along with a loud sound of friction, cracks will appear on the surface of the pillar as a door appears for the residents of the Abyss to exit. This is the gestation phase, Stage 2, that starts up the Ascendant Elevator that will take people up before the Abyss.
Abyssal beings come from outside the Otherworld. They are beings who already had the power to go past the limits. They drop Abyssal crystals, which are something like a code. Mixing the code of humans who could not go through the limits with the ones of the Abyssal beings allows the human body to forcibly become a Transcendent, once enough is absorbed. The crystals are also used to activate the elevators to bring a person up.