Gu Yi led the way, with Bai Ru close behind, both sprinting forward at top speed. Before even taking off, Gu Yi had already flicked his wrist, shooting out three talismans that flew almost simultaneously toward the mass of greenish mist, chanting the incantation to activate their effects as they went.

Two of the talismans, upon entering the fog, immediately erupted in a burst of intense flame. Gu Yi’s target was the unknown entity at the core of the mist; if he could shatter it, excellent, but if not, he intended to at least impede it.

The third talisman created a sudden gale at the edge of the mist. The "whoosh" of the wind howled through the sewer, continuously scattering the death qi that was converging into the green mass, forming a barrier at its periphery, attempting to stop the mist from expanding further.

As the wind rose, a rolling thunder suddenly erupted from within the green fog, and silvery, snake-like lightning could faintly be seen dancing within the haze—that was the other talisman Gu Yi had fired in earlier, now activated.

This exchange was swift, precise, and ruthless. In the blink of an eye, the pair had raced past the leading edge of the green fog. At this moment, the fog had not yet completely enveloped the entire sewer; there was still a distance of about one man’s width between it and the wall they were hugging.

Their pace did not slacken; they moved forward almost pressed against the wall, flying past in the strong wind, desperately hoping to pass through before the green fog consumed the entire passage.

Unlike moments before, they could not spare attention for the ground beneath their feet. Occasionally, a foot would land on the remains of a recently decayed corpse, causing a slip. Coupled with fighting against the strong headwind, their progress was clumsy and chaotic—a rare display of disarray for them.

Just as they were about to clear the green fog, Gu Yi sharply sensed several powerful gusts mixed within the gale suddenly rushing toward him. They moved so fast that he had no time to react. His only recourse was to spin, wrap his arms around Bai Ru, and drop low, tucking their bodies in to evade. The moment he crouched down, several partially decomposed animal carcasses, missing limbs, shot over their heads. The claws on their ragged limbs seemed like grappling hooks. Gu Yi heard several tearing "shrieks" close to his ears as gashes were ripped into the back of his clothes.

Once the powerful gusts subsided, Gu Yi and Bai Ru immediately sprang up, ready to continue running, only to find that the few corpses that had leaped over them turned instantly upon landing and lunged toward them again.

The speed of these reanimated corpses was startling, as if they were truly alive. Bai Ru dared not be careless; she raised her Demon-Subduing Staff and brought it down in a series of chops and strikes, batting away the corpses lunging at her. Just then, Gu Yi felt a strange sensation underfoot. Looking down, he saw a lizard, several bones showing through its rotting hide, opening its wide jaws to snap at his ankle. Had its extended tongue not brushed against his sock, Gu Yi might have entirely missed this creature.

Never having encountered such a vicious cold-blooded animal, Gu Yi’s hair stood on end involuntarily. Though he hated to admit it, snakes and lizards were truly his weak points.

Fortunately, he wasn't truly paralyzed by fear. He managed to lift a foot and drive a solid kick into the lizard's neck, sending it flying into the distance.

"Move fast," Gu Yi urged. He noticed that the agile undead corpses couldn't appear in large numbers all at once—perhaps the entity controlling them from behind had limited power. Seizing this brief window of opportunity, he pulled Bai Ru along and they resumed their desperate run.

The two supported each other, nearly rolling and scrambling to escape the range covered by the large green fog, leaving it behind them.

Unexpectedly, just as they burst out of the range, a tremendous "crackling" sound erupted from the green fog behind them, like the sound of massive tree branches snapping.

As the sound echoed, Gu Yi and Bai Ru suddenly noticed the gale that served as their barrier began to diminish slowly. Moreover, the Heavenly Thunder Talisman Gu Yi had fired into the fog seemed to have lost its efficacy; the faint rumble of thunder had somehow vanished.

Gu Yi felt a twinge of surprise. Whatever lay within, it seemed anything but easy to handle. The thought barely crossed his mind—this was no time for analysis. As they prepared to run forward again, the scene before them forced them to halt.

Not far ahead, numerous assorted animal remains—more accurately, skeletons—were scattered across the path. To charge through meant facing a fierce brawl.

Gu Yi was about to cast a spell to clear some of the immediate threat when the snapping sound behind them ceased, replaced by a deep, heavy "huffing" sound. The sound was immensely amplified by the sewer acoustics, making it seem as if a giant were panting heavily right behind them.

Gu Yi whipped his head around to look back, his expression instantly shifting. The mass of greenish fog had coalesced into a shape. The churning mist surged and roiled, vaguely resembling a humanoid form, with discernible head and limbs. The rolling green vapor continuously morphed into faces all over its body. Though each visage was distinct, every expression was one of intense agony.

Bai Ru did not turn around, her eyes fixed on the horde of skeletons ahead. She held the Demon-Subduing Staff horizontally across her chest, taking the moment to activate the spiritual power previously infused within it. Immediately, the runes on the staff flared, emitting a faint silver glow.

Seeing the death-qi-condensed humanoid figure nearly complete its formation, Gu Yi’s body trembled. He reached out, pushed Bai Ru, and commanded, "Charge."

Immediately, two more talismans materialized in his hand. He flicked them out—two more Heavenly Thunder Talismans—which transformed into twin blue lightning bolts that pierced the chest of the green figure. The mist was violently blown open, creating a large hole that it could not immediately mend or reform.

A sound like tearing cloth erupted from the fog, followed by a violent, intensified churning. The materialized green figure actually swung its arm down toward Gu Yi and Bai Ru.

Gu Yi felt a surge of powerful wind in the air. The mist-formed arm seemed almost substantial, descending upon them with massive force.

Fortunately, at the very moment he launched the Thunder Talismans, he and Bai Ru had already lunged forward. The blow missed, but the impact of the arm striking the ground sent out a shockwave like a massive wave, forcing the two forward with an involuntary stagger.

However, this setback did not prevent them from dealing with the frontal assault of corpses. As Bai Ru regained her footing, she smashed a serpent skeleton—which was little more than bones—with one blow. Gu Yi, meanwhile, cleared a path using his Five Elements Spells while unleashing Heavenly Thunder Talismans behind them almost without regard for cost.

"Keep moving ahead, we can't deal with the thing behind us right now!" Bai Ru shouted to Gu Yi while batting away the advancing corpses with her staff.

She had also noticed the massive green humanoid behind them. Seeing the faces constantly forming and dissolving on its body, a thought flashed across her mind, and she suddenly grasped the origin of the thing lurking behind them.

With enraged souls as its core, countless strands of death qi converged to form a body. Only the 'Accumulated Grievance Death Realm' could supply such an abundance of pure death qi. Those fleeting faces formed by the mist were the vengeful spirits of several students who had died tragically at the school.

They didn't know the exact name of this entity, but they were certain of one thing: it was definitely a product derived from Dark Sorcery. Unlike typical malevolent ghosts or spirits, this thing seemed extraordinarily resistant to talismans. In such a rushed confrontation, it was impossible to engage it head-on relying only on a few charms and Bai Ru's staff.

Bai Ru and Gu Yi rapidly cleared the obstacles in front while sprinting forward, all the while monitoring the movements of the green humanoid behind them. They observed that the creature was actually pursuing them. Although it was a product of condensed mist, it didn't drift in the air like fog; instead, it writhed forward like an insect.

Bai Ru’s sharp eyes spotted countless rotten, desiccated animal corpses peeking out from the very bottom of the mist mass. These acted as the foot-like appendages, constantly propelling the entire cloud of fog forward.

The "sandy" friction sound made by those corpses dragging against the ground seemed to grow steadily closer to them.

Gu Yi kicked a dog skull away and yelled to Bai Ru, "We need to pull some distance on that thing, otherwise we can't use our big moves."

Bai Ru didn't have time to reply, as the swarm of corpses lunging at them from the front had grown denser. Perhaps because they were moving farther away, the corpses in this particular stretch had not been affected by the earlier concentration of death qi.

She swept her Demon-Subduing Staff sideways while chanting, "Azure Dragon borrows the law, Qi transforms into ten thousand swords, Vanquish!"

The staff blazed with silver light, condensing power into thousands of fine needles that shot out like an impending rainstorm. Instantly, nearly every one of the numerous corpses ahead was struck multiple times, some a dozen times. The needles exploded the moment they pierced the undead flesh, causing the struck corpses to dissolve into shreds. Stinking, putrid blood splattered the ground like spilled ink.

The remainder were thoroughly battered by Gu Yi using several rounds of his Five Elements Spells. Essentially, the path ahead was mostly cleared, but the colossal entity behind them was now only about an arm's length away. Twice, its misty arm nearly crushed them.

Gu Yi said to Bai Ru while running, "I just thought of something that feels wrong. Have you realized anything?"

In such dire circumstances, Bai Ru managed to force a faint smile, saying, "We... might have run past it..."