When Meng Chao resurfaced, the sewage treatment station in Horizon was already in a mess.

As large amounts of bubbles gushed out of the filthy river water, the air was filled with a choking and pungent smell. From time to time, clusters of colorful firelight would appear, like numerous ghosts baring their fangs and brandishing their claws. They were dancing above the guards’ heads.

Meanwhile, the tremors in the cave were getting more and more intense. A ton of rock powder and crushed stones fell from the cave ceiling with crackling sounds. They smashed onto the biochemical refuse reactor’s metal outer wall, causing a series of clanging sounds that were even more terrifying.

Accompanied by a series of hair-numbing cracking, crisscrossing rifts appeared on the rock walls around the cave like spider webs.

Although the initial cracks were only as thick as strands of hair, they expanded at an astonishing rate. Soon, they upgraded from “hairs” to “centipedes,” then from “centipedes” to “poisonous snakes,” and finally, from “poisonous snakes” to “giant pythons” with hungry stomachs. They were staring at everyone and trying to devour any who were curled up underground from all directions.

Even the metal tanks that had been firmly installed on the base of the reinforced concrete trembled slightly as the vibrations intensified.

The originally smooth running whir suddenly became a stutter, while a few of the metal s emitted a hair-raising explosive sound from within.

A few of the metal tanks that had been repaired and welded were once again crushed by the high temperature and high-pressure poisonous gas from within. It went on until they exploded, shooting out streams of poisonous fog that resembled sharp arrows.

Many surveillance cameras were shaking their heads, and a multitude of instruments was rotating out of control. Ear-piercing beeps could be heard from countless alarms, and the lights above the people’s heads began to flicker crazily. The emergency lighting system that was as red as blood had automatically been activated. However, the light that poured down like a blood-colored waterfall still caught the guards off guard. Their increasingly solemn expressions revealed traces of panic.

Monsters also added to the chaos. They had always been more sensitive to earthquakes than humans.

A large number of deformed snakes, insects, rats, ants, water spiders, and water monkeys that were hibernating on the riverbed, formed a black mass of monsters. They swarmed toward the sewage treatment station before the first bubble that smelled like sulfur broke the surface of the underground river.

These monsters did not have strong offensive and combat abilities.

Normally, they would not dare provoke the human guards. Fierce high-level beasts would even be imprisoned and tortured in the laboratory.

However, driven by their desire to survive, they instinctively wanted to get as far away from the restless associated mineral vein as possible.

Compared with the Crystalline Nine-headed Dragon and other powerful, but rare, Apocalyptic Beasts, the snakes, insects, rats, and ants that were as revolting as slugs and as numerous as cow hair were on a different level of trouble.

Horizon’s elite guards had fought the most ferocious monsters in the depths of the jungle for many years.

With a light kick, the shock waves around the soles of their feet could stomp dozens of snakes, insects, rats, and ants into a paste.

The problem was, there were currently too many snakes, insects, rats, and ants.

Moreover, there was no clear direction of attack at all.

They just ran around like headless flies.

Even if they could not tear apart the humans’ iron walls, it was likely that they would drill into the depths of the sewage treatment system.

They would end up in the crisscrossing pipes, in the blind spots of the human eye, and die there. They would quietly rot and ferment, forming flammable and explosive biochemical bombs!

That would bring great trouble to the sewage treatment system’s subsequent operations.

These men, who had once fought ferocious Hell Beast, never batted an eyelid even when their ribs were broken and could even hold on tightly to their broken ribs. Yet, they could only bite the bullet and curse in the constantly shaking cave. They stepped on bugs, killed mice, and killed ghostly entities that had several pairs of wings. Flies did not look like flies, cockroaches did not look like cockroaches, and locusts did not look like locusts.

The best part was that Meng Chao saw a huge crack from the river to the rock wall. After winding and twisting, it actually extended toward the hole where the sniper, whom he was most afraid of, hid.

The rock layer around the hole was about to twist and distort, squeezing the hole to the size of a fist.

The sniper did not want to be squeezed alive into a can of lunch meat.

He could only crawl out of his hiding place, partially in a sorry state and partially in anger.

At this time, the rock wall behind the sewage treatment system suddenly shook nonstop.

The rock wall, which looked exactly the same as the surrounding cave walls, shrank and sank inward, revealing a dark tunnel.

Dozens of workers in full chemical suits and silver gas masks rushed out.

They carried a lot of equipment to monitor the earthquake’s magnitude and trend.

There were also a few prospectors in diving suits who were ready to dive into the underground river to explore the source of the earthquake.

At the same time, they brought higher-level chemical suits and gas masks to the guards.

After all, the river water was boiling, the metal tanks were cracking, and blood, as well as acid, spewed out of the twisted snakes, insects, rats, and ants after they were stepped on until their intestines burst. Although they quickly evaporated, the cave was poorly ventilated, hence it was filled with a deadly poisonous fog.

To Meng Chao, it was a pleasant surprise.

He had originally thought that he would spend some time before he could find the entrance to the Blood Flower laboratory!

Since it had revealed itself, the next step would be simple.

Meng Chao closed his eyes before he silently calculated and waited.

As the earthquake’s magnitude gradually increased, the damage to the cave continued to worsen. Not only were there crisscrossing cracks on the surface, but the rock layers underneath were also torn and dislocated. As a result, the pipelines that were buried in the rock layers were cut off.

The conventional lighting system had long since been disabled, but the scarlet emergency lights remained flashing.

Every 3.7 to 3.9 seconds, two-thirds of the emergency lights would be extinguished, causing about 55% of the cave area to fall into extremely low-visibility darkness.

The process would last from 0.3 to 0.4 seconds.

For a warrior like Meng Chao, 0.34 seconds was enough to take a comfortable hot bath, eat a hearty meal, and take a nap to recover his energy!

Thus, when the next bout of darkness came, everyone’s attention would either be on the snakes, insects, rats, and ants that were running around randomly, or on the metal tanks that were trembling crazily and whistling, or on the index and needle of the instruments that were jumping and rotating crazily.

Meng Chao was like a shadow. He jumped up from the underground river, brushed past everyone’s blind spots, and moved forward for a full ten meters. He went under a sewage pipe that led directly to the underground river, in a gap that was at most the width of a palm!