As the community who were able to control the power of manipulating soil color, shape and power, and size by reaching at specific levels of mastery.
This community had a king name yoonmin who was the only person who reached the these levels by practicing more and more. He become the superhuman of the earth community. As earth is made up of air and water there were some hidden marbels into the core of mountains which can only retrieved by the yin and yang marbles.
And these yin and yang marbles were created by the two spiritual couples who were detained from supreme realm because of having romantic connection between them.
As supreme realm is the place where all people over there are not allowed to live like a couples and these two were detained on earth to live like a human beings and ended up like a human beings but there were marbles of air and water inside them which returned to their original place as the core of the mountains.
Yoonmin( ruler of earth community) was aware of that if the yin and yang born again his power will be pused down because of them. He decided to cutt every single person from sun and moon community. As yin and yang were the ruler of sun and moon.
As sun and moon are not able to be so close to each other that couple died releasing the power stone between them.
Yoonmin gave order to his right hand ( minhu) to destroy every single home to not letting the birth of yin and yang.
But who can gi against the fate that is already written. As when devil become powerful there will always someone who will gonna make the devil down to his knees. And those were the yin and yang.