There are as many worlds out there as there are stars in the sky. However, all of them exist in a different Time and Space. Normally, they would never be able to interact or even come to know of anothers existence.

That all changed when in a distant Time and Space, a group of people discovered a way to detect and interact with them. This led to milleniums of fighting, slaughter and subjugation as the Empire expanded. However, as time passed, the method to travel between the different Time and Space was leaked to the races that had been enslaved. With great care and careful planning, over the next millenium, they staged a rebellion with the help of the worlds that had not been subjugated yet.

That marked the end of a reign of terror and the World of Elun was created. It did not exist in any Time or Space, it existed outside of it and there, all of the matters regarding the Worlds were decided by their representatives, the Summoners.

Now, when thousands of years have passed since the founding of Elun, young Jack Lumi gets picked as the new Summoner of Earth.