The earth has had an element called "Lumilight" since ancient times, and there are trace amounts of this substance in the air. An appropriate amount of Lumilight can help genetic evolution and accelerate the survival of species. However, if it is excessive, unpredictable mutant organisms will be produced, often causing huge changes in species distribution.

The incident happened in Pomrizio, a high-tech country that was "nuclear neutralized" by the coalition forces due to certain changes. After the land was bombed by nuclear bombs, a large amount of Lumilight was detected like a volcanic eruption, and the people called it "the anger of the earth." In order to deal with the increasing number of mutants and mutant creatures due to the rising concentration of Lumilight, the government launched the "Soil Rehabilitation Project": elevating the residence to a thousand meters in the air, away from the Lumilight on the surface.

There is a shortage of various supplies in high altitudes, the most serious of which is energy. Fortunately, scientists have discovered that Lumilight can be used as a new energy source that is not inferior to nuclear energy. But you need to go to the dangerous old surface to defeat mutant creatures to obtain it. So the government began to recruit and train "Lumilight Masters", a new profession that specialized in exploring the old surface and collecting Lumilight to exchange for money for the government. Players need to form a team of three light collectors and advance towards the dangerous old surface.