Under the activation of the Sun and Moon Marks, the power of the Dragon Pool surged inward like a torrent.
This time, Yang Kai deliberately restrained the two marks, only to find it wasn't particularly difficult. Zhuozhao and Youying had surely considered this when they first bestowed the marks upon him—now, with but a thought, he could modulate the intensity with which they drew power.
Even so, the volume of Dragon Pool energy being pulled in was staggering.
They were, after all, tens of thousands of zhang deep within the Dragon Pool, where the ambient energy was incomparably dense. Even the slightest draw set off a cascade like a collapsing mountain or a surging tsunami.
Fu Guang let out a low growl. His massive dragon body trembled as before, every scale bristling upright, instantly transforming into a bottomless abyss that swallowed the incoming torrent of power whole.
Yang Kai, enclosed at the center of Fu Guang's coiled body, had been somewhat tense at first—but he quickly realized he'd been worrying over nothing.
Every last drop of the drawn-in Dragon Pool energy was consumed by Fu Guang, with not a trace leaking toward Yang Kai's side.
Seeing this, Yang Kai subtly increased the marks' output, pulling in even more power.
He stepped up the draw incrementally, and only when the marks were operating at roughly seventy percent did Fu Guang finally reach his limit.
Fu Guang gave Yang Kai a slight signal, and Yang Kai understood immediately. He increased the marks' power a bit further, and with Fu Guang's cooperation, the excess energy flowed over to Yang Kai's side, where he could absorb and refine it.
Several days passed without incident. Both Yang Kai and Fu Guang silently adjusted to the mounting pressure.
Yang Kai discovered that without the yin-yang energy from Zhuozhao and Youying to grind and temper the power, he could no longer fully refine the Dragon Pool energy he absorbed, no matter how much he drew in. A significant portion was wasted, returning to the pool rather than being incorporated into his body.
It was nothing like before, when the yin-yang millstone had ensured that no matter how much energy he channeled inward, he could absorb it all without leaving a single drop behind.
That was precisely why he had been able to advance to Ancient Dragon so quickly and grow his dragon body to six thousand seven hundred zhang in a single leap.
Now, stripped of that assistance, Yang Kai finally grasped how grueling dragon lineage advancement truly was. No wonder Fu Guang had spent five thousand years deep in the Dragon Pool without breaking through.
If it was this hard for a six-thousand-seven-hundred-zhang Ancient Dragon like himself, let alone for Fu Guang, who was only a single step away from Sacred Dragon.
Yang Kai didn't know whether this trip would help Fu Guang shatter that final barrier, but since Fu Guang had asked, the best he could do was try his utmost and leave the rest to fate.
Unlike Yang Kai's situation, the spectacle of Fu Guang absorbing Dragon Pool energy was far more dramatic.
Yang Kai could clearly hear the dragon veins within Fu Guang's body roaring and surging like raging rivers. Not only that, but his surface would periodically burst open, spraying dragon blood into the void.
It was plainly the result of pushing himself to his absolute limit.
Yet despite his wretched appearance, Fu Guang's expression showed no trace of despair—only exhilaration.
The reason was simple. Before Yang Kai had entered the Dragon Pool, Fu Guang had already been employing the ancient vein-tempering method to draw in vast quantities of Dragon Pool energy, attempting to break through his own shackles.
But after five thousand years, progress had been negligible. His dragon body had reached a kind of ceiling—impossible to grow any further. The only way forward from here was to ascend to Sacred Dragon.
In five thousand years, he had considered the problem from every angle.
The ancient method itself was sound. The problem was that the amount of Dragon Pool energy he could draw in was insufficient to meet the demands of his advancement.
That was why, upon seeing the Sun and Moon Marks on Yang Kai's dragon claw, the idea had taken root—if Yang Kai could lend him a hand, the opportunity to break through might finally be within reach.
And the results proved it. The power drawn in by those two marks far exceeded what he could pull using the ancient method alone. Over the past few days, he had begun to feel subtle changes stirring within his dragon veins. He couldn't yet see the hope of a breakthrough, but any change at all was a good sign.
The worst thing would be no change at all.
If this attempt truly succeeded, it might open up an entirely new path for the dragon race going forward!
Throughout the ages, the dragon race had produced a fair number of Ancient Dragons, but Sacred Dragons had been vanishingly rare—never more than three in a single era. The primary reason was that final, seemingly insurmountable step.
If he himself could ascend to Sacred Dragon this time, then the next time another Ancient Dragon among the clan sought to break through, they could simply ask Yang Kai for help.
Perhaps the number of Sacred Dragons in the dragon race could then reach an unprecedented height.
With such thoughts running through his mind, his gaze toward Yang Kai was as though he had stumbled upon a priceless treasure.
Several more days passed. Both Yang Kai and Fu Guang had now fully acclimated to the current level of pressure.
Fu Guang suddenly opened his mouth and spat out his Dragon Pearl.
The pearl was roughly the size of a human head, perfectly round and flawless, its surface an immaculate snow-white.
Yang Kai possessed a Dragon Pearl as well, but compared to Fu Guang's, the two were simply not in the same league.
Fu Guang's pearl appeared, on the surface, to have no remarkable quality beyond its beauty—yet Yang Kai could sense from within it a devastating, world-ending power held in check.
It was the crystallization of Fu Guang's entire dragon might.
To the dragon race, a Dragon Pearl was akin to a demon beast's inner core—the very foundation of one's being, and simultaneously a lethal trump card. Should one face a formidable enemy, the Dragon Pearl could be deployed offensively.
Naturally, doing so carried enormous risk. No ordinary demon beast would resort to wielding its inner core unless it was a matter of life and death.
Yang Kai had once done exactly that to slay the Lord of the Exile Winds, and the result had been his Dragon Pearl nearly shattering—it had taken over a century of recovery before he was restored to health.