The Heavenly Dao explained, "This universe is divided into three levels of worlds. The God Realm and the Immortal Realm are vast and unique, each a world unto itself. Below the Immortal Realm, however, lie three thousand small worlds. Cultivators from these small worlds, once they reach a certain level, can ascend to the Immortal Realm and continue their cultivation."
"But," it continued, "the levels of these three thousand small worlds differ. There are five grades in total, classified mainly by the average strength of the beings within them.
In fifth-grade small worlds, most beings have lost the ability to cultivate. Even the strongest among them possess only slightly more power than ordinary humans. In some fifth-grade worlds, the top cultivators may not even reach the initial stage of Qi Refinement.
Some fifth-grade small worlds have taken a path called technology. If technology develops to its extreme, it can leverage external forces to elevate the world's grade."
Yun Jin nodded.
By this reasoning, the world Senior Brother once came from before crossing over should've been a fifth-grade small world.
Seeing that Yun Jin understood, the Heavenly Dao continued, "One level higher are fourth-grade small worlds. Most fourth-grade worlds follow the martial path. If their cultivation reaches its peak, they might even shatter the void, which would be equivalent to the Tribulation stage."
Yun Jin had actually been to fifth- and fourth-grade small worlds before.
It was just that back then, she hadn't considered the classification of small worlds, but the Heavenly Dao laid it out clearly this time.
"Next are third-grade small worlds, which is the level I currently occupy. If cultivation here reaches its peak, one can directly access the Immortal Realm. Among the three thousand small worlds, this level is considered average."
The Heavenly Dao spoke calmly, "As for that Outer-Realm Demon World, it's truly among the top-tier worlds within the three thousand small worlds."
"The energy intensity of the Outer-Realm Demon World can sustain living beings' cultivation up to a level equivalent to the Jinxian stage of the Immortal Realm. Beings from those top-tier major worlds, once they ascend, can immediately reach a mid-level power tier within the Immortal Realm. Because of this, their chances of survival after ascension are much higher. While we commonly just say 'Immortal Realm,' its full name should actually be the Immortal-Demon-Spirit Realm. The human race ascends to the Immortal Realm, the demonic races ascend to the Demon Realm, and spirit beasts ascend to the Spirit Realm. Within the Immortal-Demon-Spirit Realm, there are several major powers, and their founding ancestors almost all originated from… Rank One small worlds.."
Yun Jin frowned.
She hadn't expected the energy limit of the Outer-Realm Demon World to match that of a Jinxian in the Immortal Realm!
Normally, after a cultivator ascends, they become a Tianxian. Tianxians have nine true stages. One must progress through all nine to reach the Jinxian level.
As the Heavenly Dao said, once someone reaches the Jinxian level, they're already at medium power in the Immortal Realm.
Beings from third-grade small worlds, after ascending, must climb step by step from the first Tianxian stage to the ninth, before breaking through to become a Jinxian.
But first-grade small world cultivators ascend as Jinxians immediately.
The starting points are entirely different.
Yun Jin realized she had underestimated the strength of the Outer-Realm Demon World. After comprehending the Primordial Five Elements, she could overpower the Eight Great Demon Gods in terms of cultivation path.
But in raw strength? She might still fall short.
And that's not even counting the countless other powerful demons in the Outer-Realm Demon World. How could she handle them all alone?
Once the two worlds converge, this small world will have no ability to resist. Destruction will be the only path. No wonder the seniors of Wushuang Sect didn't hesitate to sacrifice themselves.
Yun Jin suspected that the late Master Wan Dao Saint had glimpsed even a fraction of the Outer-Realm Demon World's terrifying strength.
Her expression grew grave.
No wonder a mere fragment of a Demon God could stir such a storm, and wield so many extraordinary techniques. The Outer-Realm Demon World's cultivation techniques were probably on an entirely different level from this world.
It was a world… at true peak strength!
This small world was still far too weak.
Seeing Yun Jin's serious expression, the Heavenly Dao said slowly, "Actually, the grade of a small world can be elevated."
"Oh?" Yun Jin perked up, all ears.
The Heavenly Dao said calmly, "The stronger the overall strength of a world's inhabitants, the more powerful the world will become. Once it reaches a critical point, the small world can advance in grade.
Recently, because you've driven an overall improvement in human strength, I've sensed the threshold of a second-grade small world."
Yun Jin's eyes flickered. She had done quite a lot recently.
First, she improved cultivation techniques, boosting human cultivators' power. More importantly, she taught body cultivation techniques to ordinary people.
In this small world, mortals vastly outnumber cultivators. By raising the power of mortals, the entire human race grew stronger!
These two efforts had slowly strengthened humanity.
"Although the overall improvement is gradual, if there were millions of years to develop, I might have a chance to become a first-grade small world," the Heavenly Dao said.
The only problem was, even if she prevented the Demon Sovereign from opening the space barrier, in a thousand years, the Outer-Realm Demon World would inevitably converge with this small world. They didn't have millions of years to develop slowly.
Yun Jin's eyes flickered. Suddenly remembering something, she asked, "Could this be the ultimate secret you promised to reveal before?"
The Heavenly Dao fell silent.
After a long pause, its voice sounded again, "It's related, but not just that. Your current strength is insufficient, thinking too much won't help."
Yun Jin raised an eyebrow.
Her strength… still isn't enough?
It seemed the secret the Heavenly Dao wanted to reveal was indeed terrifying.
Yun Jin stopped dwelling on it. She said, "Anyway, I need the coordinates of the Outer-Realm Demon World first. Then, I'll take a little trip there."
The Heavenly Dao warned calmly, "Going alone will be dangerous."
Yun Jin raised an eyebrow. "I can't just wait to die a thousand years from now."
She had to go to the Outer-Realm Demon World. Staying in this small world, her strength had plateaued. Only by venturing there could she continue breaking through and grow stronger. Only then could she secure a fighting chance for everyone when the cataclysm arrives in a thousand years.
The Heavenly Dao spoke slowly, "I may be destined to perish, but you are not necessarily so. I can send you to the Immortal Realm. Once your cultivation matures, you can go to the Outer-Realm Demon World and avenge the beings of this world."
It was a rational suggestion.
Even with all its preparations, in countless simulations, this small world still only had one path: destruction.
A thousand years is a long time for mortals, but for a world, it's too short. It couldn't possibly grow strong enough to resist the Outer-Realm Demon World.
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For more information about the world and its hierarchy you can read chapter 'The Hierarchy of Worlds' on my Xianxia Handbook!