Enter the world in the mirror to help the Mirror Kings

No one knows when it happened, but the Kunlun Mirror lost some of its clarity and is unable to precisely reflect reality. Adding to this trouble is the fact that some of the mirror kings have disappeared as well. It is thought that the reason behind these problems is due to the "delusions" created by human beings in the real world. When those "delusions" were reflected in the Kunlun Mirror, they turned into various odd life forms and interfered with the normal operation of the Kunlun Mirror.

To solve the Kunlun Mirror crisis, the mirror kings began calling real-world human beings into the Kunlun Mirror to assist in dealng with the problems created by the delusions in the human mind.
This is why players are called to the mirror world.