The Myriad Beast Seal clearly possessed an extraordinary suppressing power over beast spirits. Regardless of their strength or size, once those flying beast spirits were locked down by the Myriad Beast Seal, they could not break free at all, and were drawn into the great seal one after another before vanishing.
Yang Kai could clearly see that even beast spirits comparable to twelfth-grade demon beasts were being dragged inside.
Ruoxi's going to hit the jackpot this time. Once they left, the Myriad Beast Seal's power would skyrocket to who-knows-what level.
As this thought crossed his mind, Yang Kai's expression darkened again. This was the Tomb of Myriad Spirits, and he still had no idea how to get out of it. He wasn't even sure whether tearing through space would work here.
Clatter, clatter, clatter…
The countless beast spirits roamed and crashed about, shattering the bone mountain into pieces. Endless white bones crumbled into powder with each impact.
A dim, faint yellow glow suddenly caught Yang Kai's eye. Curious, he reached out and pulled the glowing object toward him, catching it in his palm. It was cool and smooth to the touch, round and plump, and a rather decent wave of energy immediately transmitted from it.
"An inner demon core!" Yang Kai's eyes lit up with surprise.
This was actually the inner demon core of a demon beast. Judging from the energy fluctuations, it appeared to be a tenth-grade demon core at least.
He stood there stunned for a moment, not sure what thoughts had crossed his mind, but his entire being suddenly became incredibly excited. He reached out and swept his wide sleeve, and a fierce gale erupted without warning.
Whoosh, whoosh, whoosh…
The bone mountain collapsed. Countless beast bones turned to flying ash and scattered in every direction, as though a white storm had sprung up from the ground. And at the very center of that storm, a clear area roughly a dozen zhang across was left behind, with several dozen inner demon cores of varying colors lying in a jumble across the surface.
"Ha ha ha!" Yang Kai couldn't help but burst into hearty laughter. Staring at those dozens of demon cores on the ground, he laughed until tears nearly formed in his eyes.
Zhang Ruoxi had been diligently sealing beast spirits, but she had also been observing Yang Kai's movements. Seeing this now, she cried out in her sweet voice, "Sir, could it be that the inner demon cores of those demon beasts after death all remained here too?"
"That must be it. Ruoxi, we've really struck it rich this time!" Yang Kai replied gleefully, then collected those several dozen inner demon cores from the air.
These several dozen demon cores varied in quality, but the lowest were ninth-grade, and the highest reached the twelfth grade.
Countless demon beasts had perished within this Tomb of Myriad Spirits. After death, their souls transformed into beast spirits that guarded this place. Their physical bodies dissolved into motes of light and vanished, but their inner demon cores were preserved completely intact.
There was no way to count how many beast spirits there were, and likewise, there was no way to count how many inner demon cores lay here!
Inner demon cores of demon beasts had many uses, the most common being in alchemy. Many spirit pills required demon beast inner demon cores as auxiliary ingredients for refinement. Yang Kai had accumulated a great deal of rare herbs and spiritual medicines in his possession, and if he could obtain a sufficient number of demon cores here, he would have far more options when it came to refining spirit pills.
He had previously thought that Zhang Ruoxi's arrival here had granted her an extraordinary opportunity, but who could have guessed that this opportunity would fall upon his own head in the blink of an eye?
If he truly swept this tomb clean of all its inner demon cores, what an impossibly vast fortune that would be? He suspected that even the ten Great Emperors would be green with envy.
After collecting those several dozen demon cores, Yang Kai waved his hand again, sweeping aside a stretch of nearby bones. Several dozen more demon cores of varying quality immediately appeared on the exposed ground.
Over there, Zhang Ruoxi was working diligently to seal the beast spirits, while Yang Kai was equally busy collecting inner demon cores. Each of them had their own task, and neither interfered with the other. They were cooperating seamlessly.
At first, Yang Kai would sweep the bones aside, but after a while he found it tedious, so he simply released his divine sense to locate the positions of the hidden demon cores, then fired off golden blood threads to retrieve them from beneath the layers of bones. This spared him from kicking up an unholy mess everywhere.
His efficiency increased dramatically in an instant.
Before long, all the beast spirits in the vicinity had been sealed by Zhang Ruoxi, and the inner demon cores within a radius of over a dozen li had been scoured clean by Yang Kai. Though he hadn't counted them precisely, there were certainly over ten thousand demon cores.
Among those ten thousand, even if twelfth-grade demon beast cores made up only one percent, that would still be over a hundred twelfth-grade demon cores — each one worth a fortune beyond compare.
"Let's go! Find another spot!"
The area was now empty — no more beast spirits, no more demon cores. Yang Kai immediately grabbed Zhang Ruoxi and relocated. As for how to get out… they could figure that out after they'd wrung the place dry first.
Above another mound of bones, Zhang Ruoxi summoned the Myriad Beast Seal while Yang Kai released his divine sense to search for the demon cores hidden beneath the skeletal remains.
In less time than it took to drink a cup of tea, this area had been swept clean as well. Without a word, Yang Kai bundled up Zhang Ruoxi and shifted to yet another location.
They swept through one area after another. The beast spirits were sealed clean by Zhang Ruoxi, and the inner demon cores were stripped bare by Yang Kai. For the first time since the Tomb of Myriad Spirits had come into existence, it had likely suffered such an upheaval.
This was nothing short of outright robbery!
If the Four Great Sacred Spirits of the Ancient Wilds ever learned of this, who knew what they would think.
There were no sun or moon here, no distinction between night and day. However, Yang Kai estimated that he and Zhang Ruoxi had spent roughly three days in this place, and in that time they had covered nearly the entire tomb.
This was presumably a small, isolated world, not particularly vast in area. The reason the two of them had spent three full days here was primarily for sealing beast spirits and collecting inner demon cores. Had they simply flown through at full speed, they could likely have traversed the entire tomb in less than an hour.