Outside the underground ancient city, more than twenty monks of the four sects who practiced qi and advanced ranks, under the leadership of the four foundation building period monks, stopped on a pile of rubble.

"I really didn't expect that this underground ancient city is so big, no less than the capital on the ground, and looking at the architecture of this ancient city, it is quite similar to the capital above, the outer is an ordinary house, and the inside is an inner city, could it be that this underground ancient city was once also the capital of a country, and the inner city is the imperial city?" The young foundation building period monk of the Nine Formations Sect looked at the ancient city in front of him, and his eyes showed a hint of thought.

"It shouldn't be possible for a country's capital, after all, the history of the Jiang Kingdom's mortal kingdom for thousands of years and nearly 10,000 years has been traced, and I have never heard of any country where Kyoto has fallen underground!" The white-robed foundation builder of the Ten Thousand Swords Gate shook his head slightly.

"Stuck underground? Hehe, I'm afraid that Daoist friends have guessed wrong, this ancient city should be built directly underground. The black-robed old man of the Demon Sect smiled and looked at the ancient city with a strange look in his eyes.

At this time, several other foundation building period monks couldn't help but look over, and even the golden-robed Taoist priest of the Ascension Star Sect also looked sideways slightly.

"Daoist friends have seen something, can you tell me about it!" The white-robed young man of the Ten Thousand Swords Gate raised his eyebrows, and asked directly.

"The old man only thought of a secret vaguely recorded in the sect, which was related to the disaster of the entire immortal cultivation world ten thousand years ago, as for the truth or falsehood, the old man couldn't confirm it. The black-robed old man of the Demon Sect sniffed his nose, took a sharp breath of the surrounding gas, closed his eyes and felt it carefully.

"The catastrophe of the Immortal Cultivation Realm tens of thousands of years ago, but that invasion of the Ancient Demon Realm!" the young man of the Nine Formations Sect exclaimed, asking in disbelief.

"Apart from that ancient demon invasion, what else can be called a disaster in the immortal cultivation world!" the black-robed old man nodded.

"Brother Dao, don't sell it, I've all heard of the invasion of the ancient demons, but does the invasion of the ancient demons have any connection with this underground ancient city? Could it be that this ancient city was built by those ancient demons?" The white-robed young man of the Ten Thousand Swords Gate frowned and continued to ask.

"According to the records of the sect, the main target of the invasion of the ancient demons at the beginning was not our Dibei, but the Jin Kingdom of Middle Earth, and our Dibei was only carried by the invasion, but even so, my Dibei is still unable to resist the invasion of the ancient demons, and the immortal cultivators of the entire Dibei Immortal Cultivation Realm have died more than seventy percent, and in the end, only some major sects have fled overseas with the remnants of their forces, which has made the Dibei Immortal Cultivation Realm not extinct. And after the northern part of the country was invaded by those ancient demons, many mortals were enslaved and created a lot of demon kingdoms, I think this underground capital is the capital of one of the demon kingdoms, so as to explain why this capital is not in the records of the sect, after all, at that time, the human monks had lost control of the north of the earth. The black-robed old man explained word by word, and at the same time looked at the ancient city with a little more fire in his eyes.

It's no wonder that this black-robed old man is a cultivator of the Demon Sect, and his cultivation is all demonic skills, this underground ancient city is related to the ancient demon clan, maybe he can leave something related to the demon clan, which may be extremely helpful to their demon cultivators.

"The country name Yue, the territory covers the three countries around the Jiangguo, the ancient demon clan invaded the north three years later, the royal surname Ye, existed for more than ten years, and then disappeared overnight because of unknown reasons, and at the same time disappeared more than a million mortals, it turned out to be here. The golden-robed Taoist priest of the Ascending Star Sect looked at the ancient city, and his eyes were full of some inexplicable looks.

Hearing the golden-robed Taoist priest of the Ascending Star Sect suddenly say this paragraph, the other foundation building period monks were all surprised, they all turned their heads to look over, with different expressions in their eyes, they all didn't expect that the Taoist priest surnamed Li actually knew a lot about the ancient city, and even the black-robed old man of the Demon Sect was also surprised.

"This matter is not a secret, more than ten years ago, Li had received a bounty task from his uncle, which was to sort out the detailed information of the ancient demon invasion, which was slightly mentioned in this demon country, and then all those materials were included in the fifth floor of the library as anecdotes. The golden-robed Taoist priest explained with an unchanged face.

"Since the two Daoists know some details, then this underground ancient city may really be left by the demon kingdom 10,000 years ago, then we should be even more careful in this underground activity, after all, those ancient demons can't even be helpless by the ancient monks of 10,000 years ago. The monk of the Ten Thousand Swords Sect said with some seriousness.

"Although this ancient city is left by the Demon Kingdom, the Demon Kingdom is also composed of mortals, and it is not much different from the current mortal country, so what is there to be afraid of! The old man just doesn't believe it, ten thousand years have passed, and there are still ancient demons surviving?

"Fellow Daoists, it's better to be careful, it's not entirely impossible for the ancient demon clan to survive 10,000 years ago, isn't it an example of the two demons who came out of the Demon Cliff thousands of years ago! The young man from the Nine Formations Sect quickly followed, opening his mouth to explain, while glancing slightly at the golden-robed middle-aged Taoist priest.

When the other foundation building period monks heard the foundation building youth of the Nine Formations Sect mention the two ancient demons from a thousand years ago, their faces changed color for a while, and even the black-robed old man of the Demon Splitting Sect also stopped, his brows furrowed slightly.

The ancient demon who cultivated the immortal realm for disaster thousands of years ago is not a secret, and the slightly larger sects in the north of the earth have some records, and the monks in the foundation building period present all have some understanding, even some Qi cultivation period monks also know some generally.

At this time, the monks who remembered the rumors of the ancient demons thousands of years ago all inadvertently glanced at the monks of the Ascension Star Sect a few more times, and there was some inexplicable meaning in their eyes.

According to records, the predecessors of many Yuan infants in the north of the earth entered the Falling Demon Cliff treasure hunt of the ancient monks and the ancient demons who fought ten thousand years ago, but they were the two ancient demons who accidentally released the seals inside.

After the demon was born, a group of primordial infant monks in the Demon Cliff gathered to besiege the two ancient demons, but found that they were not his opponents at all, and they were almost killed by the two ancient demons.

In the end, it was the legendary figure of the Ascending Star Sect who made a move, and one person blocked one of the ancient demons, and killed the ancient demon, which alleviated the crisis, but after all, he couldn't leave another ancient demon and let him escape from the Falling Demon Cliff.

After that, several great cultivators in the north of the earth led more than ten ancestors in the infancy stage to lay down a forbidden array to besiege the escaped ancient demon, and finally killed the ancient demon, otherwise if it was allowed to develop, it would definitely be a catastrophe in the earthly north immortal cultivation world.

"That Demon Cliff is the place of the ancient war, so that some high-level ancient demons can be preserved, but this is just a small demon capital, and there will never be that kind of ancient demons. The black-robed old man of the Demon Sect frowned, and looked at the ancient city not far away with some uncertainty.

"Brother Dao, the ancient demon clan are all fierce people, where do you need high-level ancient demons, but if there are one or two low-level ancient demons, we are afraid that we will not be able to deal with them, we should be careful in everything, and we must not take it lightly!" The young foundation building stage monk from the Nine Formations Sect added.