The underwater world they found themselves in reminded Zac a bit of Twilight Ocean, but there were some poignant differences as well. For one, the water was actually water, rather than an odd fusion of Life and Death. Secondly, the place was extremely sinister, where at least a third of all plants and beasts had poisonous attributes.

Seeing as the realm was a solid Middle D-grade Mystic Realm, even Zac found it hard to deal with some of the toxins that could appear out of nowhere. Some rocks turned out to be venomous shellfish that spat bullets of poison, there were almost invisible strings in the water from dangerous jellyfish. And all the while, dangerous predators roamed the ocean for targets to feast on.

Somewhat ironically, the dangerous environment also helpt them keep safe. Both the venomous and normal beasts in this place knew all-too-well how dangerous this place was. In a place where everything could contain deadly toxins, you stuck to feeding on what you knew was safe. Thanks to that, most of the beasts didn’t go out of the way to attack them and only struck when they felt threatened.

Unfortunately, the plantlife didn’t share this wariness. There was no surface in this realm, with the whole area enclosed in a rocky wall like a subterranean lake. With the high energy density, the edges were covered in all kinds of plants, some of them reaching hundreds of meters. For example, there was a vast swathe of extremely toxic seaweed that blocked their path on the second day of their travels.

The forest generated a deadly domain that stretched for tens of miles, and the two had been forced to delve deeper into the Mystic Realm rather than skirt around the edge as they usually did. And even discounting the plants and the beasts, there were still dangers in the toxic sea. There were even pockets of poisoned waters seemingly without a source.

Zac was constantly in a feverish state while his body worked overtime to deal with the toxins. But as bad as he had it, Vai had it far worse. If not for the various talismans and treasures Leyara had provided, she wouldn’t have survived a day in this place. Even then, the two were forced to occasionally stop and rest to deal with the toxic buildup.

Any thought of pilfering treasures like before had long since been discarded. Unique toxic plants had a steady demand on the outside, but it wasn’t worth it. The more valuable a toxin was, the likelier it was that harvesting it would get them killed. If anything, they wanted to stay clear of anything that looked unique or valuable.

Even with all the challenges, they made decent progress through the realm. But on the fifth day, something changed. A deep and sustained rumble made the whole ocean shake, and some of the powerful currents were turned into enormous maelstroms.

“A breach?” Zac muttered as he looked around with a frown.

“I can’t sense any energy fluctuations,” Vai hesitated. “It shouldn’t be- WHAT IS THAT?!”

Zac’s head snapped around, and his hair stood on end when he saw what had shocked Vai so badly. It was a chaotic and all-consuming dark-green wave of putrefaction coming toward them, drowning everything as it covered the whole horizon. Where it had come from, Zac had no idea, but it didn’t matter.

What mattered was what would happen if they were swallowed up, and he had the misfortune to see it firsthand. A silvery fish had been knocked back in the chaos as its shoal desperately tried to swim away. It was swallowed by the green cloud, but it immediately shot out again. But a single mistake had sealed its fate, and the peak E-grade beast started rotting away at a speed visible to the naked eye.

Seeing the scene, Zac wordlessly grabbed Vai as he fled through the waters with all the speed he could muster. He even activated his Dao Field with Spiritual Void to cut through the resistance, giving him a small advantage. It barely allowed the two to outpace the calamity, but even then, Zac wasn’t happy.

The earthquake was only gaining in power rather than waning, which made Zac wonder if they had only seen the tip of the iceberg. Vai clearly understood the problem as well, and she did everything in her power to figure out a solution, from scanning various missives to observing the surroundings.

Unfortunately, their fears were soon realized as they saw a second poison tide come at them from the left, soon joining the first one.

“This is bad!” Vai cried. “This calamity will drown the whole realm.”

“There is no way we’ll reach the waystations in time.” Zac frowned as he looked around. “Do you have any ideas?”

“I- I-“

“Stay calm,” Zac said as he pushed a wave of life-attuned Dao through her body to help clear her head.

“That’s- There are so many beasts that live here. If this is a recurring event, there have to be safe spots,” Vai said. “Should we follow some of the fishes, perhaps?”

“Alright, good enough,” Zac nodded, praying that this was indeed a recurring tide rather than something brought by the recent instability of the Void Star.

“Those there,” Vai eventually said as she pointed to a shoal. “I have seen their kind all over, yet they don’t seem very powerful. They move in a straight direction as well.”

“Alright,” Zac nodded and changed course, following in the wake of the fleeing beasts.

The minutes passed, and it started to feel more and more likely these beasts understood something about what was going on. Not only were they making a beeline in a certain direction, but after an hour, two more shoals had fused with the one they followed.

“Look to our right,” Vai suddenly whispered, prompting Zac to glance over.

It wasn’t a third cloud – not yet, anyway. But the whole field of view had started to darken, and Zac guessed it wouldn’t be long before they only had one safe direction remaining. His eyes thoughtfully turned back to the fishes who desperately swam in the only safe direction.

“What if-” Vai hesitated with worry.

“If it comes to that, we’ll figure something out,” Zac muttered. “Worse comes to worst, we’ll force open a spatial rift and escape. That usually works.”

“That’s impossible!” Vai immediately said. “A chaotic tear is not something you can just- Wait, what do you mean usually?”

“Up ahead,” Zac said, ignoring the last comment.

Their worst fears, that they would be surrounded by the toxic clouds, were thankfully not realized. There was finally a change in their surroundings – a volcano, by the looks of it. Seeing it made Zac’s eyes light up. Was this how the fish dealt with the situation? Simply stay within the protective layer of the magma which burned the toxins before they reached the depths?

At least the other beasts seemed to think so. Zac saw one pack of beasts after another dive into the caldera as well. Soon, it was their turn to enter, but Zac and Vai didn’t heedlessly follow the beasts. And it was lucky as well as they saw a tragic scene below.

It wasn’t a volcano they had stumbled onto, at least not one in the traditional sense. There was something molten-looking below, but it rather looked like quicksilver than magma. Not only that, but it emitted a weirdly ominous aura, something that was only reinforced by the thousands of unmoving bodies that bobbed across the surface.

They had all been covered in the quicksilver, making them look like gilded statues rather than carcasses, so Zac and Vai had no way to see how the beasts had died. They couldn’t even sense what kind of energies the quicksilver contained, it was somehow shielded or isolated.

“Have you heard of something like this before?” Zac frowned.

“No, but I… I think it is alive,” Vai said after some hesitation. “It’s not a mixture, it’s either a sentient pool or innumerable miniature creatures.”

“What?!” Zac blurted as he gave the pond a second look, just in time to see the shoal of silvery fish shoot into the quicksilver.

The area around them suddenly shimmered and Zac sensed powerful Dao-fluctuations that made him think of the ocean and crashing waves. The insights didn’t seem very deep, but the field around the shoal was amplified by the thousands of fish. Zac looked on with interest, realizing they used their Dao to contend with whatever the quicksilver was. And it seemed to work – Zac saw how a depression around the Dao Field appeared as the beasts pushed into the depths.

Even then, they soon saw a steady stream of silvery unmoving fish reach the surface. The beasts were dying by the hundreds over the next minute until there finally was nothing. All in all, almost two-thirds of the beasts had perished, but that also meant a third somehow survived. Seeing as there were no more gilded fish getting pushed to the surface, there should be a safe spot somewhere in the depths.

“Alright, looks safe enough,” Zad nodded as he started to descend toward the shimmering surface.

“Safe? Most of them died,” Vai cried, but she still followed close behind.

“Are you ready?” Zac asked when the two floated right above the surface. “Don’t let the liquid touch you. Be ready to take out that thing of yours if it breaks through.”

Vai quickly nodded, and the two unleashed their Dao Fields the next moment, with Zac even using Spiritual Void to boost his even further. Unsurprisingly, the power of Zac’s three boosted Dao Branches far eclipsed Vai’s newly evolved Dao, but her control was clearly better. She was able to create a field no more than two meters across, while Zac’s stretched for over twenty since he simply was unable to condense it any further.

That way, she formed an inner layer of defense in case his were breached. And thankfully, it worked just like it did for the fishes – far better even. The two sank further and further as they kept watch of their surroundings. It really looked like the liquid was alive. All around them, tendrils tried to push through the superimposed Dao Fields to get to them, yet they were continuously rebuffed.

The quicksilver tendrils that stayed inside too long lost their luster and fell apart, and not one came even close to reaching Vai’s inner domain. It looked like Dao Branches were enough to keep this thing at bay, allowing them to focus on finding a safe spot.

It took them two minutes, but they eventually discovered a tunnel leading further into the depths, and a few dozen beasts stuck at the ceiling of the path proved they were moving in the right direction. Deeper and deeper they went, swimming under a trail of unmoving animals. Eventually, the path bent upward again. Soon after, the quicksilver turned into pristine waters again, though the tunnel kept going for a while longer.

Both of them immediately extinguished their auras upon emerging. His danger sense told him in no uncertain terms something terrible was waiting at the end of the tunnel. Then again, one didn’t need a massive pool of Luck to sense the discordant but immense aura from up ahead. It seemed quite dangerous, but even then, they continued.

Beasts would keep coming from behind, and the path was easily big enough to accommodate Beast Kings. This was not a place they could stay, so they carefully inched their way toward the mouth of the exit until they saw what they were dealing with. A quick glance indicated there were no toxic clouds around, proving they had made the right decision coming here.

Even then, Zac almost wished they hadn’t.

Zac wondered if this was any better as he looked at the chaotic mix of beasts that were crammed together in a hidden underwater basin. Most of the innumerable beasts were E-grade, but there were well over a hundred monolithic Beast Kings squeezed together as well.

Herbivores and predators, weak and strong. All were silently sharing the limited space. Suddenly, a three-meter piranha snapped up a smaller eel next to it with a lightning-quick motion, swallowing it in two big gulps. But the moment it struck, the dormant auras of the Beast Kings rose, and the closest one effortlessly impaled the piranha with its tongue.

A gulp later, the piranha was gone and silence had returned to the basin. It looked like there was an unwritten rule of cohabitation in this place – the moment someone acted up. It looked pretty weird, but Zac had an idea of why. The ambient energy was incredibly sparse, no doubt a result of so many beasts being crammed together.

If beasts started to fight and cause a ruckus, the energy might run out before the danger outside had passed. After all, even if a Beast King entered hibernation, it still required some ambient energy to survive.

Zac didn’t know why the Beast Kings didn’t just kick out all the weaker ones that competed for the limited resources, but perhaps they had some long-term considerations. If the toxic clouds outside killed everything in the realm, and the Beast Kings ate the rest of them in here, then the Mystic Realm would eventually become a wasteland with only a few solitary leaders roaming the depths.

And so, the Beast Kings became the guarantors for survival in this place. Of course, Zac wasn’t very confident humans would be afforded that kind of protection as well.

A powerful aura suddenly appeared below them, and both Zac and Vai pushed themselves against the tunnel wall as they sealed their Cosmic Energy. A moment later, an enormous snake pushed through the silvery liquid, its head alone reaching over twenty meters. It was clearly another Beast King, and even if Zac was confident in dealing with it, there was no way he could do so without alerting the swarm just outside.

So Zac’s heart beat like a drum as the enormous head came closer. Suddenly, the beast stopped, and a massive tongue flicked in the water as it looked back and forth. Vai was pressed into the wall right next to him, and he could feel how she barely managed to stop herself from shaking. The snake stayed like that for a few seconds, seemingly looking for something, but it thankfully moved away after a while.

Soon enough, the beast had pushed into the enormous tangle, leaving Zac and Vai to live another day. Even then, Zac felt his hair stand on end after the encounter.

“A- I,” Vai whimpered before she clamped her mouth shut.

“Shh,” Zac whispered as he pointed upward.

Vai looked up with confusion, and she gasped with relief. Most of their vision was blocked by the swarm, but they could somewhat see a weak shimmering light refracted through the surface of the water. There was actually a surface in this place, which might mean land and a safe harbor from this terrifying Gordian knot of underwater creatures.

The two didn’t want to wait for another Beast King to show up, so they slowly made their way toward the surface, extremely cautious to not create any ripples in the water or leak even a speck of energy. It was slow and extremely arduous, but their trek thankfully didn’t seem to garner any attention. A few of the nearby beasts glared at them suspiciously, but they restrained their bloodthirsty impulses out of fear of reprisal from the Beast Kings.

Soon enough, they were right at the edge, allowing the two to breathe out in relief. Even if they were targeted at that point, they’d be able to make it out of the water quick enough. Better yet, Zac could already somewhat glean that there was ample space above-water. But just as Zac was about to breach the surface, he felt a sharp pang of danger as he saw a blurry line descend toward them.

A golden laurel appeared above his head and Verun’s Bite, and two golden bubbles appeared just in time to block out a sword strike that had come out of nowhere. There was someone who had not only seen their approach but also tried to kill them. Unfortunately, that was the least of their worries.

The depths below churned as a response to the outburst of Cosmic Energy, and the sinister cultivator above had even thrown in a couple of cracked Nexus Crystals that leaked energy into the waters. One towering aura after another spread through the basin, and Zac sensed multiple Beast Kings immediately lock onto them.

They were exposed.