At that moment, in the valley outside the mine cave.
"Kill!"
The human martial artists had completely gained the upper hand, their roars shaking the heavens.
Although those Netherhounds were formidable, the number of human martial artists was simply too great.
Furthermore, for this expedition into the Crystal Mine Small World, the top-tier factions of the Middle Continent—the Xiao Clan, the Fengyun Family, the Su Clan, the Shenfeng Sect, the Tianyan Sect, and the Hudao Academy—had also dispatched a large number of Yuan Foundation Realm experts.
The Yuan Foundation Realm experts from just these top-tier forces alone numbered close to a thousand when combined.
Thus, very quickly, those Netherhounds were forced into retreat, being constantly slain.
"Speed it up!
Those guys outside are going to charge in any moment now!"
Wen Zi kept urging Ye Yunfei and the dozens of academy students.
Every one of them was mining and collecting the Spirit Crystal Stones at their fastest speed.
Finally, a moment later...
"We've finally wiped out all these disgusting monsters! Let's hurry inside!"
Beyond the mine cave, surprised shouts and roars rang out.
Immediately after, numerous fierce figures charged towards the location of the mine cave.
"They're coming in!" Wen Zi exclaimed in alarm.
"Let it go.
We've already excavated about three-fifths of this large crystal ore vein. We won't fight them for the remainder," Ye Yunfei said after a moment of thought.
"With so many people rushing in, how do we get out?" Wen Zi asked.
"I plan to go in and take a look," Ye Yunfei said, pointing at the deep, gloomy hole from which black mist continuously billowed.
"Go inside?" Wen Zi looked at that hole with its eerie aura and couldn't help but feel a jolt of fear.
Ye Yunfei's figure flashed as he entered the hole.
Left with no other choice, Wen Zi and the dozens of students had no choice but to follow Ye Yunfei inside.
Past the entrance was an underground passage, filled with black mist and a sinister, chilling atmosphere.
"Master, you plan to see if there are any Ancient Demon Race corpses in this place, right?" Hu Miao asked via sound transmission.
"That's right.
The demonic aura emanating from this cave is extremely pure and of a high grade.
I estimate that if there are Demon Race corpses here, they must be of a relatively high level and possess considerable strength.
If used to refine bloodline essence, they would be perfectly suited for me to cultivate the sixth layer of the Heavenly Demon Blood-Merging Body Forging Technique.
That's why I want to go in and see." Ye Yunfei nodded.
"Hey! Ye Yunfei, wait for us!
This place is a bit scary!"
From behind, Wen Zi hurriedly caught up.
The dozens of students looked at one another, gritted their teeth, and one by one, quickened their pace to closely follow Ye Yunfei.
This underground passage slanted continuously downward, with sinister winds whistling through.
It was impossible to tell just how long they proceeded through this shadowy underground passage.
Then, the scenery before them suddenly opened up. Ye Yunfei discovered he had entered a massive underground world!
The area of this underground world was extremely vast. It seemed a huge space had been hollowed out directly beneath the earth and constructed into this place.
At a glance, one could see clusters of palaces, shrouded in a haze of shadowy mists, appearing deeply desolate!
"This place is so terrifying!
Could there be ghosts?!" Wen Zi clung tightly to Ye Yunfei. While afraid, she also seemed to feel a sense of curiosity and thrill.
The dozens of students also felt chills running down their spines one by one.
"Perhaps there will be," Ye Yunfei said with a laugh.
"Let's go take a look." After surveying the underground palaces ahead, Ye Yunfei lifted his foot and walked forward.
Wen Zi and the dozens of students hurriedly followed.
Heh heh...
Suddenly, a chilling sneer came from the distance, filled with a malicious flavor.
"Be careful! Stay close to me!"
Under the perception of Ye Yunfei's Soul Power, he detected several black shadows radiating evil auras hiding in the darkness in the distance.
Wen Zi and the dozens of students were all apprehensive, carefully following behind Ye Yunfei.
Heh heh...
Soon, that malicious sneer sounded again.
Then.
Whoosh!
A black shadow abruptly appeared, carrying waves of a fierce and ghastly aura as it pounced through the air to attack at high speed.
"Master, it's a Ghost Bat!"
Hu Miao's voice rang out.
"Correct.
It's a Ghost Bat." Ye Yunfei nodded.
Under his Soul Power perception, Ye Yunfei could see clearly. The black shadow was a giant bat, covered in black scales and sporting a fierce demonic face.
Its eyes blazed with extremely malevolent light.
Its pair of claws flashed with a cold gleam, shrouded in fierce, swirling energy, resembling a pair of iron hooks.
Ye Yunfei pointed a finger, and the Void Blade shot out, slashing towards that Ghost Bat.
Screech!
The Ghost Bat emitted a piercing, strange cry and engaged the Void Blade in fierce combat.
This Ghost Bat's movements were extremely swift, moving back and forth like a jet-black bolt of lightning.
However, the Void Blade, controlled by Ye Yunfei's Soul Power, was also incredibly fast.
Moreover, the Void Blade could move through space, appearing and disappearing unpredictably.
For a time, the Void Blade and the Ghost Bat were locked in a stalemate, neither gaining the upper hand.
Whoosh! Whoosh...
Several more Ghost Bats charged over from the dim surroundings.
With a thought from Ye Yunfei, five spirit swords shot out, forming a Five Elements Godslayer Sword Array to slice and crush through them.
A moment later...
Screech! Screech...
Those few Ghost Bats suddenly let out pained cries. Already injured, they immediately scurried into the darkness and vanished.
"Be careful.
This place has many Yin-type creatures."
After cautioning Wen Zi and the dozens of students, Ye Yunfei continued walking forward.
After walking for a while longer, they encountered a flock of strangely-shaped crows. These crows were entirely black, had human faces, and their cries were extremely unnerving.
Each one possessed strength equivalent to the early or middle stages of the Yuan Foundation Realm!
Ye Yunfei recognized them—these were Ghost Crows.
Activating the Heaven-Shadow Robe, Ye Yunfei personally took action, charging forward. With one punch per crow, he blasted the entire flock into oblivion.
"Master, I suspect this place is an underground mausoleum.
The Yin Qi is too heavy, giving birth to many spectral entities," Hu Miao communicated to Ye Yunfei.
"Correct.
This is a Yin Land," Ye Yunfei said with a nod.
Having once been a Heavenly Emperor, Ye Yunfei's knowledge was vast. With a single glance, he could tell that this underground world had been specially arranged to gather Yin Qi.
"A Yin Land?!
I've heard Yin Lands can nurture corpses. Is that true?" Hu Miao asked.
"Correct.
Yin Lands can indeed nurture corpses," Ye Yunfei confirmed.
"I want to see just who arranged this Yin Land," Ye Yunfei stated.
Following that, Ye Yunfei led Wen Zi and the dozens of students further forward.
Soon, they approached the cluster of palaces ahead.
"Let's go in and see."
Ye Yunfei walked up to one palace, gave it a look, and prepared to enter.
Suddenly.
Rumble rumble...
In the distance, the ground shook violently with tremendous rumbling noises, as if thousands of troops and horses were charging forth.
Then.
Squads upon squads of cavalry, clad from head to toe in armor and wielding gleaming long spears, riding on black warhorses, charged forward through the billowing haze of Yin mist.
"Yin soldiers?"
Ye Yunfei couldn't help but frown.