Billions of years ago, the Seven Realms were prosperous and strong people could easily cross the realms. But excessive prosperity leads to crisis - the law of entropy.
Practitioners from all walks of life continue to create new laws and new supernatural powers, causing the world's origin to be overburdened. Finally, the Seven Realms began to "slide" toward the original chaos and were about to merge into one again.
At this time, the seven strongest men discovered the secret of "Xu". They used themselves as sacrifices to create the Ruin Sea, a huge buffer layer under the Seven Realms. The sea of xu will slowly swallow the redundant laws overflowing from all walks of life to maintain balance.
As a price, the seven most powerful men were transformed into boundary pillars, and they remained on the Ruins Sea forever. They are revered as the "First Generation Ruins Emperors"
