Magic Flux is a device created by the atia towards the end of the fabled Age of Wonder, while at the height of their power. Physically it resembles a giant wheel some 20 feet in diameter, with eight spokes branching inwards towards a central hub.
Built primarily out of legendary Spirit Wood, and imbued with bands of enchanted metals, the magic flux was built to hone and harness magical energies from miles around. Its purpose was to increase the magical potential of the atia, supplying them with all the energies they needed to perform their experiments and spells. It was highly successful in doing so, and the atia hung it above their greatest city, Allyon, where it remained suspended between two massive pillars for several years and provided the atia with all the energies they could ask for.
However, as much as the flux was a symbol of the atian mastery of magic, it was also a manifestation of their arrogance. The flux fulfilled its purpose all too well, and did not differentiate between one arc and the next. It drew within it the corruptive powers of the Black Arc, which eventually maifested itself in a way so terrible no one had foreseen it coming.
For years, the flux gathered energies, gathering more dark energies within it in ways too subtle for even the atia to see (or perhaps they choose not to see, for the flux provided benefits many could not think to do without). One black, stormy night, lightning struck the flux, and unleashed the six chkarth into the world from the turbulent realm of Inferis.
In the years that followed, the charth gathered demonic forces and led an invasion which almost caused the destruction of the entire world in a cataclysmic event called simply The Great War. The flux played its part once again, this time forming the catalyst to banish the demonic host from the world and into Inferis, and as a terrible side affect caused The Sundering, which caused terrible earthquakes that shook both kingdoms and landmasses into rubble.
In the aftermath, it was the dwarves who took the flux into their keeping. They carried it into the far north and sealed it away within their great mountain-fortress of Vordaal, therein sealing it within solid rock so that no one would ever be able to use such a powerful artefact again.