The Fifth World
Ten thousand years ago, there lived a powerful order of mages called the Horadrim. The Horadrim lived in the city of Atlantis, at the cultural height of the Greek civilization, and throughout all their lives they had suffered as the playthings of cruel and capricious gods who, it was felt, cared nothing for the suffering that they inflicted upon their mortal servants. Lead by a powerful runemage named Pythagoras, the Horadrim managed to breach the boundaries of the multiverse itself and achieve contact with an extra-dimensional being they called Pandorym. Essentially a quasi-sentient singularity following physical laws vastly different from their own, the Horadrim saw Pandorym as a viable weapon against the gods and managed to coerce the mighty being into entering the material plane. Knowing that they couldn’t control it’s full power with magic, the Horadrim managed to separate the alien being’s psyche from it’s physical body in the instant that it entered their reality, trapping the former in a crystal prison in the depths of their city and the latter safely away in an extra-dimensional prison which touches the multiverse at only one point.
Before they could begin to consolidate their position and extract demands from their tormenting gods however, Pandorym became aware that it had been deceived and managed to lash out against it’s prison; it created 4 more breaches in reality, through which it managed to strike at both it’s captors and the gods that tormented them. Malevolent and powerful, it wanted nothing more than destruction, and managed to systematically execute every member of the Horadrim and the Gods of Olympus before the breaches in it’s prison were contained by the concentrated efforts of all the other gods. The cataclysm, however, had utterly annihilated Greek civilization and forever changed the landscape of the planet.
This is the world that remains for you explore. This is The Fifth World.