The Cataclysm, also known as the N0 Cataclysm or the Upheaval (LINE Webtoons) occurred in the year D1000 (which changed into the year N0 after the event) and was named such because of a series of disastrous events: the disappearance of the primeval gods Visnu and Shiva; the destruction of various planets during a large-scale interracial war that involved gods, suras and humans; and the weakening of the bonds between gods and humans (severely reducing the success rate of the god-summoning Idha Etu magic and the amount of power humans can borrow from gods).
Some say that the disappearance of Visnu and Shiva caused the Cataclysm; some others say that their disappearance was the Cataclysm itself. The consequences were as disastrous as the event itself: the races were separated by Visnu in three different realms, thus ending the war, while many pureblood humans and quarters suffered because of the emotional resonance that made the halfs maddened against their own friends, relatives, and lovers. As a result, the halfs ended up being discriminated against and treated like slaves, sold, and killed for the consumption of their body parts without any remorse from humans.
- The Cataclysm began on a still-unnamed planet. Currygom stated that it was a different planet from Willarv, Carte, Isholy, and Konchez.
- The suras received the worst of the three realms, with a poisonous atmosphere and constant inter-clan struggles for survival and power. This environment was particularly harsh to the Gandharva clan.
- N0 is also the year of Kubera Leez's birth.