The cultivation method of demons was largely different from the methods martial cultivators used. Moreover, there would also be different methods between different demons.

The giant beast body of Jiu Ying sat in the middle of the mountains. He had almost completely camouflaged with the eerie mountain wall, with the exception of his black scales that were glowing with faint light.

His heads were arranged in a mysterious arrangement, allowing him to vaguely sense the essence of a spirit design. Clearly, this was something that had been passed down to him over generations. For demons, the best and quickest method was something that lay within their bloodline.

Wu Yu sorted out the items left behind by Ghostly Wings of the Black Mountain into five categories: immortal medicines, immortal essences, immortal treasures, other precious treasures, and any other miscellaneous items.

For those nauseating items that ghostly cultivators had created, Wu Yu left them in a Sumeru Pouch before burying them deep in the ground.

The items that were left behind were largely not useful to Wu Yu at all. For example, in the aspect of spiritual immortal treasures, the six flags used by Ghostly Wings of Black Mountain were very powerful. However, Wu Yu felt that mastering this spiritual immortal treasure would damage his state of mind. Now that he had the Nine-Directional Demon Imprisonment Column, he was content and felt that it would be sufficient.

For swords, those belonging to He Taozi and his other senior brothers and sisters were better than his. However, these were the belongings of his senior brothers and sisters after all, and he had to return them to Shushan.

Among the items carried with Ghostly Wings of the Black Mountain, there were more precious treasures than immortal essences. This might be due to the fact that precious treasures were largely materials for crafting spirit designs. Among which, most of them were metals, unique stones, and other materials used for crafting immortal treasures. There were also large numbers of blank talisman papers. These in themselves were created from precious treasures.

Precious treasures were similar to immortal essences. Those of high quality were largely gifted with spiritual marks by the heavens and earth. The more spiritual marks they had, the better the quality. In order to create extremely powerful immortal treasures, the materials and precious treasures used played an extremely important role. However, the Immortal Treasure Spirit Designs crafted on it were even more important.

Taking the Nine-Directional Demon Imprisonment Column as an example, the main material and precious treasure used had at least three spiritual marks. Moreover, a large amount of materials was needed.

There was also a large number of books on crafting Immortal Treasure Spirit Designs. Most of them were evil spirit designs used by ghostly cultivators. However, some of them were neutral. In fact, there were also books on introductions to spirit designs. Currently, Wu Yu had preliminary knowledge of refining immortal medicines. After the battle with Ghostly Wings of the Black Mountain, he gained a strong interest in crafting spirit designs.

However, no matter how interested he was, he had to put this aside. This was because he knew clearly that the most pressing thing to do within the Supreme Hunting Ground was refine his Jindan!

Compared to his current Nanwu Treasured Moon Golden Vajra Body, the Jindan essence of his Jindan was far from sufficient. Although a tough body was great, his Jindan and his cultivation level were the core of cultivation. Wu Yu was clear about this.

He sat with his legs crossed deep within the cave. With Jiu Ying guarding outside, he could devote all his attention to refining his Jindan.

Ghostly Wings of the Black Mountain had left over 3,000 Golden Essence Pills behind. This made Wu Yu feel as though he was overflowing with wealth. With his current body strength and toughness, he could safely withstand the explosion of power from consuming Golden Essence Pills. At this moment, even his Sea of Breath Meridian was incomparably strong, and his white-colored Jindan was highly compressed. Therefore, Wu Yu had no qualms with consuming Golden Essence Pills as though he was consuming nuts, so he gobbled down one after another.

Within his dantian, the Great Way of Immortality Art was already activated. It started capturing, fusing, and even devouring the medicinal energy of the Golden Essence Pills. After which, the boundless medicinal energy was dissected and segregated. The core essence energy was then converted to parts of the Jindan little by little.

Although he was consuming Golden Essence Pills at a very fast pace, Wu Yu's body and Sea of Breath Meridian were still in a very stable state. Even when the medicinal energy of the Golden Essence Pills raged like a beast in his body, it couldn't even make a tear on Wu Yu's body. Wu Yu's current body could easily be classified as made of steel.

This was also a result of a strong physical body.

Sensing intense energy disruptions behind him, Jiu Ying lifted one of his heads and glanced at Wu Yu. He couldn't help but gasp. "This guy is really a monster in a human body. He's even more demon-like than the demon race."

When he first met Wu Yu, he didn't know there was such a sick and insane side to Wu Yu.

"I have accidentally dragged him into this. Hopefully, he can leave safely eventually," Jiu Ying thought to himself.

However, as time passed, he became even more astonished. Initially, Jiu Ying had thought that Wu Yu was just starting off with consuming Golden Essence Pills to aid him in cultivation. To his astonishment, Wu Yu had been relying fully on Golden Essence Pills to refine his Jindan. When a day passed, he had refined over a hundred Golden Essence Pills. The speed and intensity in which he was refining them was completely exceptional and unbelievable!

"He's the real demon compared to me...!" Jiu Ying sighed emotionally. At the same time, he was greatly motivated by Wu Yu. He focused his mind and accelerated his pace.

Wu Yu was fully devoted to refining his Jindan and was using Golden Essence Pills to test out his current limits. He paid attention to the quality of his Jindan at all times to ensure that it remained in the most concentrated form. He didn't tolerate any careless mistakes, and he would immediately stop if he noticed that his Jindan couldn't withstand the rapid increment.

The improvement in the toughness of his physical body had brought him huge advantages. The control over the medicinal energy of the medicine became easier, which then made it easier for the Great Way of Immortality Art to refine his Jindan. During the entire process, there wasn't a single hiccup.

For Wu Yu, this was only made easy due to him accumulating strength for a long time. The Great Way of Immortality Art was an exceptional path to immortality. The extent of neutralizing Golden Essence Pills through its Jindan Condensation Wondrous Art was something that couldn't be matched by other Immortality Art.

10 days later, Wu Yu had consumed over a thousand Golden Essence Pills. The wealth he had a hard time earning had shrunk by one-third all of a sudden.

However, such a loss had its rewards. The white Jindan in him had expanded constantly and had gotten stronger during refining with surging energy. Eventually, Wu Yu completed a major metamorphosis and reached the fourth tier of the Jindan Dao Realm.

Boom!

Jindan essence shrouded his body and his immortal fire burned even more vibrantly. Although he was just a fourth tier Jindan Dao cultivator, Wu Yu had exceeded many fifth tier Jindan Dao cultivators in the aspect of Jindan essence.

Together with his Nanwu Treasured Moon Golden Vajra Body and two of the 72 Styles of Transformation, his strength had definitely made a huge leap forward!

Hu!

Wu Yu stopped consuming Golden Essence Pills and instead focused on consolidating his fourth tier Jindan power. After a few more days, he finally stabilized his current cultivation level. At this moment, his Jindan had already grown much stronger.

The fourth tier of Jindan Dao Realm is indeed different! As he had just consumed a large number of Golden Essence Pills, he would have to rely on cultivation to refine his Jindan and make it even more compressed in the future. At the same time, he would have to strengthen his foundation. Moreover, it was said that from the fourth tier of the Jindan Dao Realm and onwards, just having the Jindan Condensation Wondrous Art wouldn't suffice. He would still have to rely on his body's ability to understand and carve out a path, or even a dao, that was suitable for himself. After which, he would have to incorporate this into the process of refining his Jindan.

"The advancement from the fourth tier of the Jindan Dao Realm to the fifth tier involves one achieving a single state with his dan. Otherwise, even a person like me with lots of Golden Essence Pills wouldn't be able to advance that quickly. It seems like the fifth tier of Jindan Dao Realm is truly a watershed."

Now that he had just reached the fourth tier of Jindan Dao Realm, Wu Yu didn't think that far into the future. He didn't have any plans of being one with his dan at this moment. Nonetheless, he knew that cultivation wasn't simply about mechanically training his body, cultivating a spiritual source, and refining his Jindan. As he approached the higher tiers, how and what a person thinks, what one understood with his heart, one's connection with the heavens and earth, and one's mental state would play a bigger role. These were areas that even the Invincible Vajra Body and Great Way of Immortality Art couldn't help him with.

This was because one probably needed to have his own dao to become an immortal. Without a dao, how would there be Immortals?

An Immortal Dao that belonged to himself would also be something different from the legacy that Wu Yu had inherited.

"Congratulations on your huge increment in strength," Jiu Ying said sincerely in his human form as he walked in.

It was then that Wu Yu noticed that Jiu Ying's cultivation level had also strengthened after just a dozen plus days. This guy was indeed the son of Ying Huang! He was completely different after just a few days!

"What are your plans moving forward?" asked Jiu Ying.

Wu Yu pondered for a moment before answering, "It's still early. Jiang Zhuyue doesn't know about my strength level yet. I'll be aiming to make more improvements before this fact is exposed, even if it means me staying here for one or two years."

Wu Yu made an estimation. For him to quickly obtain 50 Demon Injunction Orders, he would likely need to be at least in the fifth tier of the Jindan Dao Realm and pick up a Great Dao Mystique. Perhaps he might even need to be at the sixth tier. As for those demons in the 10th Hunting Ground, Wu Yu estimated that he would at least need to be in the seventh tier of the Jindan Dao Realm to be able to defeat them.

It would be best to quickly gather 50 Demon Injunction Orders before being sent to the Ninth or 10th Hunting Grounds. This was his plan and therefore he required more strength.

As for how Jiu Ying's path would turn out, he did not have a clue at all and couldn't influence him. Would Jiu Ying be imprisoned here for life?

"You are right. Since we do not have a better solution, constantly increasing our own strength wouldn't be a bad thing. I used to be lax in my cultivation in the past as I felt that I could easily overtake all the other demons. However, Wu Yu, you have brought me great pressure. Looking at how quickly you are improving has motivated me. I can't lose to you!" Jiu Ying remarked confidently.

So he had reached his current cultivation level at such a young age with a lax attitude towards cultivation! Wu Yu really envied him.

"Alright then. Let's spar and see who has improved more just before I leave the Supreme Hunting Ground," Wu Yu replied with a smile.

"That's a deal. Don't regret your current actions then!"Jiu Ying instantly got excited and filled with ambition.

"What is said can't be retracted," said Wu Yu calmly.

"In that case, I shall not waste any time." After finishing his sentence, Jiu Ying ran out and transformed into his demon form to absorb the essence of the heavens and earth to strengthen himself. More and more spiritual qi in the atmosphere was devoured by him.

Truthfully speaking, although the Endless Demon Seas was shrouded in darkness, the density of the spiritual qi in the atmosphere wasn't any inferior to that of Shushan. It was just that it wasn't as concentrated as that of the Clear Sky of Shushan.

"My father is the strongest demon on the divine continent. There's no way I'm afraid of you!" Jiu Ying was filled with passion and was fervently looking forward to that day in the future.

As for Wu Yu, he wasn't particularly in a rush.