Nao was a legendary humongous one-legged divine beast with horns atop its head. 

It was rumored that it wreaked havoc in the sea before being exterminated by the overlords. The Yellow Emperor was said to be among them.

Nonetheless, it was a legend, so there was no way to verify its authenticity. Yang Chen had heard of that divine beast but never dared to imagine that it once existed until he saw the drum. 

Due to Nao’s talent in controlling lightning, the drum made from its skin was an extremely powerful artifact. 

Yang Chen asked in astonishment, “How did you recognize it at first glance? Have you seen it before?”

“Of course not. But the Qingqiu clan has books that have been passed down from the Great Ancient times, so I’ve seen some descriptions of the Nao Drum. It seems like the Great Ancient Immortals placed the Nao Drum here 40,000 years ago. No wonder the Ziqing Heavenly Lightning is so powerful. As it turns out, it came from this divine artifact.”

“Eh?” Luo Xiaoxiao seemed to have discovered something. Pointing at the Nao Drum, she remarked, “Look, there are so many Ziqing Heavenly Lightning bolts around the drum, but when we go near them, they seem to retreat.”

Yang Chen and Yu Xuening took a closer look and realized she was right. 

The Ziqing Heavenly Lightning dodged them as they approached, ostensibly allowing whoever got close to approach the Nao Drum.

Yu Xuening’s eyes lit up. “It seems like this Nao Drum doesn’t have an owner!”

“Are you saying it’s waiting for its owner?” Yang Chen asked. 

“That’s right! The more powerful the divine artifact is, the higher chance for them to have consciousness. This applies to Nao Drum. I reckon the drum still contains part of Nao’s soul. It’s similar to your Chaos Cauldron, whereby it contains Chaos’ soul. This Nao is probably waiting for someone to bring it out of the tower, so it’s willing to let us near it when it saw us,” Yu Xuening explained.

Yang Chen frowned as he recalled the Meng clan’s ancestor’s words. He said that this treasure could rejuvenate the devil cultivators. Unless… he’s referring to entering the Sky Tower and getting the Nao Drum!?

Yu Xuening grinned as if she had read his mind. "Don't oversimplify things, silly lad. This drum can control the release of the ninety-ninth level of Ziqing Heavenly Lightning on its own. It is apparent that if it is used, it will have endless power. However, no matter how powerful an artifact is, its effectiveness is determined by the master's cultivation. It would be ludicrous if devil cultivators could be revived with a piece of the relic."

Once she pointed it out, he had to admit that was the case. 

“Who cares. Just take it, Yang Chen. The Nao Drum seems very lonely here,” Luo Xiaoxiao said excitedly. 

Yang Chen was enticed by the prospect. After all, no one would want to miss out on such a treasure. Even though he had the Chaos Cauldron, Pangu Axe, and Kunlun Mirror, the more the merrier.

Yu Xuening’s eyes crinkled as she smiled. “I never use artifacts, so you can take it. However, you have to think things through. Once you take the Nao Drum, there probably won’t be any Ziqing Heavenly Lightning left in here, which means anyone can leave the tower…”

A wry smile formed on his face. “That’s the reason why I’ve yet to touch it.”

As soon as he spoke, his expression changed. Yu Xuening’s eyes lit up as well. 

“I see!” Yang Chen clapped his hands. “No wonder the Meng clan’s ancestor said it could be used to revive the devil cultivators! If the Meng clan’s descendants used this key to reach the top of the Sky Tower and take this Nao Drum, that would mean all the cultivators in the Ten Thousand Demon Realm will return to the human world. The human cultivators will be easily slaughtered!”

“That’s right.” Yu Xuening nodded. “This will definitely revive the devil and demon cultivators. In that case, the restrictions the Great Ancient Immortals placed on them would disappear. The Ten Thousand Demon Realm would not be able to restrict them.”

Yang Chen was relieved that he finally managed to sort the odd matter out. At the same time, he was nonplussed. 

Although he did not know what the Meng clan’s ancestor was like, the latter did not to his descendants. Alas, the whole of the Meng clan, and the devil and demon cultivators, have let them down. 

If they could try to fight for power in the illusionary dimension instead of hiding in the Honghuang realm, they would have had the chance to discover the secrets of the Eye of the Sky Demon and the treasures. 

Yet, they had not figured out anything despite their attempt to research the treasure. It never crossed their minds that the treasure was merely a key to bring them to glory. 

In the end, they no longer had any thoughts about the key, treating them as an amulet and letting Yang Chen benefit from it. 

If the Demon Sect had known the treasure might be used in this manner, they would have hastened to the Eye of the Sky Demon, even if it meant risking their lives, rather than remaining in the Honghuang realm.

It was probably a test from their ancestors, as the fate of the clan lay in the hands of the descendants. 

Just as he was lamenting over the situation, Yu Xuening spotted something weird and flew to the top of the Nao Drum. 

There, she saw some shining golden script. 

It seemed like someone had carved it at the top of the tower. 

Since the explosion from the fight between Yang Chen and Wen Tao did no damage to the Sky Tower, it was unbelievable for someone to be able to carve words onto it, unless it was done by the Great Ancient Immortals.  

However, Yang Chen did not recognize those intricate scripts. They did not seem to belong to China’s history. 

He flew up and asked, “What is this?” 

Yu Xuening seemed solemn for once. With a look of shock and deference, she spoke after a long silence. “This is… the Great Ancient writing system.”

Knowing that Yang Chen was unaware of it, she explained, “This writing system came from the Great Ancient times. In the old books passed down from that era in our clan, many of them are written in this writing system. Not a lot of people know this writing system 50,000 years ago as it is too complex and hard to memorize. Most of the scripts have changed but at the very least… I still recognize them.”

“What do they say then? A cultivation technique?” Luo Xiaoxiao followed along, eager to listen to the mysterious matter. 

After checking out the passage carefully, complicated emotions appeared in my eyes. In the end, she said, “This passage is about the connection between the Ten Thousand Demon Realm, Sky Tower, Eye of the Sky Demon, and the Twelve Divine Gods and Demons Array…”

Yang Chen’s mouth dropped. It was a shocking piece of news. Isn’t this the “manual”! And why is the Divine Gods and Demons Array involved!?

Yu Xuening translated the words and explained it to them briefly. 

As it turned out, the Twelve Divine Gods and Demons Array, Ten Thousand Demon Realm, and Eye of the Sky Demon were created by the Great Ancient Immortals, although they seemed unrelated. 

40,000 years ago, to seal large amounts of demons and devils, the Great Ancient Immortals created the array.

However, they soon realized that the demons and devils in the array kept resisting and increasing in numbers, which led to an overwhelming amount of Yin energy. Sooner or later, the array would collapse. 

Hence, after several searches, they discovered the Eye of the Sky Demon and the Ten Thousand Demon Realm. 

Due to the unique space structure and characteristics, it was very suitable for the absorption of the Yin energy. 

The Immortals altered the array, directing the majority of the Yin energy to the Eye of the Sky Demon. That took care of most of the issues.

However, the Eye of the Sky Demon was closed off and would one day collapse from an overwhelming amount of Yin energy. 

Therefore, they created a channel from the Eye of the Sky Demon to the Ten Thousand Demon Realm, which was the path used by Yang Chen and Luo Xiaoxiao. 

Like raindrops, the Yin energy seeped into the Ten Thousand Demon Realm from the Eye of the Sky Demon through the space passage. 

Coincidentally, the demons and devils in the Ten Thousand Demon Realm needed to be subdued, hence the creation of the Sky Tower. 

The Nao Drum was hung above the tower, as the final collection point of the Yin energy. 

As long as it was the spiritual energy, be it the Yin or Yang energy, the Nao Drum could convert it to the Ziqing Heavenly Lightning. 

With that, the three places were perfectly linked together. 

The Yin energy inside the array was absorbed into the Eye of the Sky Demon, which worked as a middleman and transferred into the Sky Tower for the Nao Drum to release Ziqing Heavenly Lightning. 

The advantage was that the Yin energy would not enter the Ten Thousand Demon Realm directly, which was probably the Immortals being compassionate so as to not destroy the environment. 

After listening to the explanation, Yang Chen and Luo Xiaoxiao stood rooted to the spot. 

It was not their first time witnessing the marvel of the Immortals’ creation, but such an elaborate and intricate “project” was simply unbelievable!

The joy he had obtained from entering the Shang Qing Heavenly Lightning stage was dispersed when he realized he was still incompetent. 

Yu Xuening’s expression was filled with awe. As she was far more powerful than Yang Chen, she could comprehend the disparity in power at a greater level. 

After a long silence, Luo Xiaoxiao blinked and softly asked, "If that's the case, aren't the Great Ancient Immortals concerned that some bad people will steal the Nao Drum and release the demons and devils cultivators? Didn't the ancestor of the Meng clan come over and take the key?"