Sole Cloud Flying Cave

Cui Heng was transmigrated to another world and the system told him that the new world he was in was a high-grade Xianxia world.
It was a world where Celestial Kings soared the sky and terrifying monsters ruled the lands. The strong would destroy a planet if their mood was bad and Cui Heng trembled in fear when he learned of how scary the new world was.
Thankfully, the system had granted him the protection that last for 300 years. As long as he remained in the safety zone, he would not receive any damage.
With his safety secured, he began his cultivation training for the next 300 years.
Throughout the years as he trained, some people entered his safety zone by mistake.
There was a peasant who was once a monk and a beggar. Despite that, he still had the dream of bringing peace to the land and saving the lives of millions.
There was a noble who was once called the once-in-a-million-year genius. Yet, luck wasn't at his side and his talent fell and was laughed at by others for years.
There was a princess whose only wish was to find her older brother. She could've become a celestial but decided to remain in the human realm to wait for her brother's return.
There was a weak lady who was plagued with illness from birth but had the goal of adventuring and helping the poor and weak.
...
Cui Heng befriended these people and even gave them a few pointers before they left.
300 years later, when the protection period had ended, he had finally mastered the Golden Core. Even then, he was still reluctant to go to the outside world.
But when he did, he realized that the world was merely a world of Wuxia.

Realizing This Is A Wuxia World After Cultivating For 300 Years

Cui Heng frowned slightly when he heard this. This Zhou Juntian was really everywhere.

More than 300,000 years ago, he was the Sage who walked out of Daozhou Star. He was the last person to ascend under the Purple Sun Heaven. He was the one who caused the Heaven Realm to send down a scarlet light and caused the Purple Sun Heaven to be destroyed. He was also once the disciple of the Purple Sun Heavenly Lord.

Even letting the Heaven Realm reopen was related to him?

Then was he also related to the sudden disappearance of the Heaven Realm back then?

Thinking about it carefully, most of the secrets and major events in this world seemed to be related to Zhou Juntian to a certain extent.

Although Cui Heng was puzzled in his heart, he remained calm on the surface and said in a low voice, "Why is Zhou Juntian related to the reopening of the Heaven Realm?"

When I Was Cultivating, There Was No Heaven Realm