Finally, Cao Yun was about to break through and to become a 4th-grade Exalted Demon. This fourth grade was a qualitative change in the Exalted Demon realm. Indeed, it was during this grade that Cao Yun would ignite his Body's Ministerial Fire, also known as the Kidney Fire. When his Common People's Fire completely filled not only his lower abdomen but also his lower back, his Mingmen would naturally begin to produce intense heat that would ignite his kidneys and produce this fire. The Body's Ministerial Fire was much closer to one's essence. As such, its ignition would immediately make the demon stronger as he would gain more vitality.
Cao Yun honestly had no idea how long he had stayed in seclusion. Just based on his cultivation speed, he thought that he had stayed around twenty-five years, but it could have been thirty or even more. He was just guessing based on his own assumptions about how long it would take to break through.
Considering that he was ready to break through, Cao Yun decided to remain in seclusion until his breakthrough. Thankfully, it happened very fast. Soon after his decision, Cao Yun sensed intense heat in his back. As a matter of fact, it actually hurt him. This heat radiated from his Mingmen and flowed through his body, going straight for his kidneys. Internally, the pressure and heat were causing a lot of pain. Strangely enough, they were also creating a deep feeling of satisfaction. It wasn't rare to feel pain and pleasure at the same time while training. Pain was sadly part of the process, but it helped build character for some.
It felt as though his kidneys were literally melting within his body. However, Cao Yun didn't lose his calm and composure. With his mind, he focused on the phenomenon in order to take everything in. Not only would it help his future asura cultivation, but it might even help him get a few pointers about the Dao of Fire. After many hours, the breakthrough was finally over. From his kidneys, a powerful heatwave spread even outside his body. This time, though, it was extremely pleasant with no amount of pain. Maybe the sudden disappearance of pain made it feel even better than it should have.
At this moment, Cao Yun had become a 4th-grade Exalted Demon. His flame was becoming blue. From now on, he had to work on his Kidney Fire to make it stronger and more plentiful. Afterwards, just like his Common People's Fire, he would have to slowly spread the Body's Ministerial Fire through his body. The process was slower because it was more dangerous. Indeed, the last of the Three Bodily Fires Cao Yun had to ignite was the Heart Fire, also known as the Imperial Fire. Obviously, any mistake here could actually destroy his heart and kill him. So there were more grades to delicately guide the Body's Ministerial Fire to its ultimate goal. Only once the Three Bodily Fires were ignited could Cao Yun merge them into his True Fire and break through to the Reborn Demon realm.
Although it was difficult to say for sure, Cao Yun thought that this would take him around one and a half centuries. Unfortunately, he would need to leave before half a century had passed. In the best-case scenario, he would be a 6th-grade Exalted Demon at this moment, but most likely still a 5th-grade Exalted Demon, to be fair.
Anyway, it was finally time for Cao Yun to leave seclusion. When he left, he was surprised to see Feng Yingyue waiting for him. Clearly, she had succeeded in her breakthrough and was a powerful 5th-grade Spirit Warrior. However, Cao Yun could see some pain on her face, she wasn't trying to hide it. And, as soon as she saw her husband, she stood up. She got closer and hugged him. Even without words, Cao Yun understood. He felt tears beginning to form, but they never flowed down his cheeks. His uncle had died while he was in seclusion.
Cao Yun visited his son Cao Bei. Cao Bei had become an abbot. In fact, Cao Bei was in charge of his own monastery. For a moment, Cao Yun thought that Cao Bei would blame him for not being there for Fang Shaolong. Contrary to his expectations, Cao Bei understood perfectly. Several people, including Cao Yun's brothers, had wanted to warn Cao Yun, but Fang Shaolong himself had asked them not to disturb him, because he was certain that Cao Yun would have left seclusion. Deep down, Cao Yun was afraid. Even he wasn't sure whether he would have left seclusion. Of course, he wanted to be certain that he would have, but a small voice in the back of his head suggested to him that he might not have agreed to stop his cultivation for anything or anyone. Unfortunately, that voice wasn't Dian Mo, it was Cao Yun himself. He had to admit the truth to himself, Cao Yun felt guilty about leaving his family alone for so long.
Considering that Fang Shaolong had died, Cao Yun stayed out of seclusion much longer than usual. For almost an entire decade, he spent time with his friends and family, explored the Hongchen Kingdom and even visited the demon territories. In fact, he even went to the Desolate Sepulcher with Hongyu. During this time, he literally secured a path through the Divine Blood Ocean. Cao Yun and Hongyu killed a couple of Stormriser Leviathan Emperors, and Cao Yun set up array formations in various places to protect the path from powerful demonic beasts. At the same time, Hongyu threatened a few demonic beasts to obey her orders. This wouldn't work for very long, but this would help the demons consolidate the path. Besides, the humans had found a way of becoming Sages, but the demonic beasts still couldn't become immortal beasts. In other words, humans would slowly become much stronger than any demonic beast. For now, though, the secret would not be leaked to the demons.
Since Cao Yun didn't want to involve himself in politics, he simply visited the people who actually had the power and made sure that everything would survive his departure. He didn't force them into anything, he just made sure that their plans and ideas weren't dangerous for the people he cared about, and for everyone else, really. In fact, Cao Yun even released the seals he had placed on the Sisters of the Abyss. After all, after his departure, they would be useless. At the same time, he was now strong enough to kill them if he wanted to, so there was no need to hold a threat over them indefinitely. Moreover, he could imagine that having this seal inside them was torture.
Everyone could tell that Cao Yun was settling his affairs once and for all. Soon, he would have no ties to the Piaolu planet except for his family. Even there, Cao Yun was taking care of things. He visited his children and their children, and their grandchildren. In fact, one of his great-grandchildren was already pregnant by the end of this decade. Cao Yun made sure to meet and to talk to all of them. Sadly, he could feel that he was more distant from them. Maybe it was mainly due to the fact that he knew that he wouldn't be present in their lives, but it was also because their connections were more distant. In a matter of centuries, if Cao Yun stayed, he would have dozens of generations of his own line. Not all of them would become powerful cultivators, but they would still live a long time. As a matter of fact, this was why humans didn't have too many children. Three kids like Cao Yun and Feng Yingyue were usually the upper limit.
Anyway, in a few centuries, there might be hundreds of thousands of humans who could be directly related to Cao Yun. Of course, many would be from different families into which a member of the Cao family had married. But this was still dizzying. Obviously, Cao Yun wouldn't feel connected to someone ten generations removed, just like he felt related to his father, grandfather and great-grandfather but could barely trace his family further. To be fair, his great-grandfather was the progenitor of the Cao family, and Cao Yun knew close to nothing about his father before him. However, he didn't care to learn more either. They were related, but at some point, everyone was related, even humans and demons had common ancestors after all.
There was one last piece of business Cao Yun wanted to settle before going to his last seclusion. He went where Cleansed Asura's body was buried. Even Matriarch Huang Yufeng had been unable to dig it out. First of all, the body was buried deep underground and was physically difficult to approach even for a powerful cultivator. The pressure and heat underground were insane for most cultivators. Moreover, Cleansed Asura's body had created some kind of barrier. During his decay, his inner world had collapsed and created the Yellow Death World that had spread around him. The remnants of this broken inner world were still there, emanating corrosive energies, most of them being Death Energy.
Cao Yun had a vague idea of where Cleansed Asura's body was based on where he had been when he had received his Drop of Wrath. The body had been buried much deeper, but his soul had been able to reach the place where Cao Yun was at the time. Besides, Cao Yun had a few positions where the Yellow Death World had been accessible. Using all of this, Cao Yun was able to find the shortest path toward the corpse. Even then, the process was long and difficult.
Despite his powerful cultivation, this required incredible effort from Cao Yun. He even wondered if Cleansed Asura had not been buried in the very core of the Piaolu planet. He wasn't even close to it, but the pressure and heat were already extreme. Finally, Cao Yun got to the body. Without any hesitation, Cao Yun put the body inside a spatial ring he had taken precisely for this purpose. After all, he wouldn't have wanted to put his master's body with random artifacts, so he had taken an empty spatial ring. In his mind, he had imagined being more respectful to his master's body, but the environment was so hostile that he had no time to be delicate or considerate.
At last, Cao Yun took Cleansed Asura's body out of the ravine. Unfortunately, he was now faced with another problem. There was no fire hot enough to cremate his master's body. Unless Cao Yun tried to go deeper underground, he had no way of burning the body as his master had wanted. Unfortunately, he couldn't go deeper because he would die himself. After all, if he found a place hot enough to burn his master's body, it would obviously be hot enough to kill Cao Yun. Although his master was dead, his body was still vastly superior to Cao Yun's.
Fortunately, Cao Yun knew exactly where he would find a fire hot enough to completely turn his master into ashes. As it turned out, Cao Yun intended to go there as soon as the conditions were met. Thus, he kept the spatial ring with him as his most precious treasure. In fact, he even hesitated to place it directly into his inner world. However, he wasn't too confident in using his inner world in such a manner for now. Sun Liao had placed the best array formations possible on the spatial ring. Cao Yun was certain that he wouldn't lose it and that no one could ever open it even if he died. Of course, an Immortal would be able to open it through sheer force, but Cao Yun had no reason to encounter such a powerful monster.
Now that everything had been dealt with, Cao Yun went back into seclusion. This would be the last time he would cultivate on the Piaolu planet for a very long while. Afterwards, he would take some time to be with his family and friends. But he couldn't fully control his time either. The portal he wanted to use would only be usable for so long.
During his last seclusion, which lasted a bit more than two decades, Cao Yun barely progressed his Dao of Fire or his Dao of Death. The second floor of his inner pagoda was complete, and he now simply needed the Pillar treasure in order to form the third floor and officially become a 3rd-grade Sage. Finally, he became a 5th-grade Exalted Demon but did not have enough time to reach 6th-grade Exalted Demon, most likely because of the decade he had spent with his family, friends, and exploring the world. Honestly, Cao Yun didn't regret anything. According to what he had read from Emperor Nuwa, he was confident that he was strong enough to go where he wanted. He would probably be stronger than anyone, but not necessarily with a crushing advantage.
When he left seclusion, Cao Yun made sure that he was right about his destination. He found the portal Emperor Nuwa had kept secret. Under the Everlasting Earth Palace, he found a large root that seemed to appear from nowhere. It was extremely strange because when Cao Yun looked at it, he simply couldn't see its end, but it clearly ended abruptly. It was similar to the branch that appeared during the Greater Tribulation. Indeed, this was a tiny root from the Withering Fusang Tree. Even though it was tiny, it was extremely large. From all of Cao Yun's research, this root was bending space and could thus allow him to go to his destination.
The Withering Fusang Domains consisted of several worlds all connected to the Withering Fusang Tree. They were more or less connected and could more or less perceive the tree. Just like the Piaolu planet, they were all connected to it, though. The actual Withering Fusang Domains were much more directly tied to the tree, unlike the Piaolu planet. From Emperor Nuwa's journals, Cao Yun knew there were six worlds revolving around a seventh world where the Withering Fusang Tree actually was.
Time and space were completely distorted. Predicting how time would be distorted was extremely difficult, but Cao Yun was able to predict when to use the portal to get to the world he wanted to visit. After checking everything, he visited his friends and family. He had to say farewell and get ready. In a few months, he would finally leave. With the time distortion, even a few decades in those domains could be centuries, if not millennia. It was almost a one-way journey.