A Fire Ox demonic beast at the sixth layer of the Foundation Establishment stage. This kind of opponent sent a chill down Lei Dong’s spine. If the situation hadn't been so dire, he would have cursed that ancient sect for being utterly senseless, setting the entry requirement at the second layer of the Foundation Establishment stage. A guardian beast for a Black Tower—they actually used a real demonic beast to fill the role. No matter how Lei Dong racked his brain, he couldn't grasp that this was simply how the Heart Demon Hall operated. It wasn't that every tower summit was guarded by an actual demonic beast. Only occasionally, when the restriction field detected a naturally grown beast within a certain area of the Heart Demon Hall that had reached a certain level, would it be teleported to serve as a guardian. This saved energy on one hand, and on the other, it spared the restriction field the trouble of having to dispatch foes against beasts that were about to mature enough to threaten the disciples.

Of course, regardless of whether Lei Dong could slay the Fire Ox demonic beast, it was fated not to survive the day the Heart Demon Hall closed. After all, if it only opened every hundred years, this Fire Ox might have grown strong enough to reach the eighth or even ninth layer of the Foundation Establishment stage. The designers of the ancient sect's Heart Demon Hall were truly meticulous and resourceful, utilizing everything to its fullest potential. It was just occasionally disastrous for unlucky souls like Lei Dong. Truly, a demonic beast possessing the actual strength of the sixth layer of the Foundation Establishment was vastly different from a summoned beast conjured by spellcraft.

As the Critical Hit Ghost Guard was hurled back, Lei Dong immediately ordered the other two Ghost Guards to retreat, strictly forbidding them from engaging in a direct confrontation. The disparity in strength was too great; close combat would be suicide. Taking a deep breath, he unfurled the Myriad Ghost Banner, and hundreds of fierce ghosts surged out, forming a chilling, soul-stirring torrent of shrieking phantoms.

Lei Dong certainly didn't expect these fierce ghosts to slay the Purgatory Fire Ox demonic beast at the sixth layer of the Foundation Establishment. To rely purely on these fierce ghosts to kill a beast of that caliber would likely require thousands of them to make a difference. All Lei Dong needed was for this horde of spirits to tie the beast down, to impose some constraint upon it.

As dark energy erupted around him and the Netherworld Great Art was deployed, Lei Dong’s figure flickered rapidly. Simultaneously, Lei Dong sealed a hand sign, launching a football-sized ball of eerie, deep-green flame, trailing a long fiery tail, straight toward the Fire Ox. The Fire Ox lived up to its status as a true demonic beast rather than a spell-conjured creature; despite its massive bulk, it twisted and leaped with surprising agility, dodging Lei Dong's Netherfire Orb.

The Netherfire Orb was a spell Lei Dong rarely used since mastering it. But using it now against this Fire Ox was not without reason. Lei Dong's goal was merely to attract the Fire Ox’s attention, not to kill it. If he had used the Wheel of Silent Annihilation, not only would it be impossible to kill the beast so easily, but the energy expenditure would also be far too great.

The moment he ordered the Ghost Guards to fall back, Lei Dong knew this was destined to be a war of attrition.

Lei Dong’s Netherfire Orb was far from perfected; its speed was slow, its cohesion weak, and its full power failed to achieve the general destructive capability expected of a Foundation Establishment cultivator. This was unavoidable; any spell, to be wielded effectively as a killer blow, required vast amounts of time for continuous practice until mastery was achieved. But Lei Dong genuinely did not have the luxury of time to dedicate to long-term practice of the Netherfire Orb. Lei Dong’s unfamiliarity with controlling the Orb was not a critical issue; with his cultivation and divine sense, he could still manage to detonate it prematurely.

Just as the Fire Ox dodged the Netherfire Orb, it erupted with a deafening explosion. The sickly green netherfire, amplified by the surrounding Netherworld Qi, surged outwards like a massive, splashing wave. Sparks flew everywhere. Although the Fire Ox avoided the core of the Netherfire Orb, it could not evade the resulting blast. However, both the shockwave generated by the explosion and the scattering netherfire were blocked by a layer of flame surrounding the beast’s hide, failing to inflict even a scratch.

But Lei Dong had succeeded in thoroughly enraging the Fire Ox. Abandoning its desire to continue attacking the Critical Hit Ghost Guard, it turned and charged toward Lei Dong, its momentum fierce and its aura overwhelmingly savage. Lei Dong, stepping on the Netherworld Qi, began playing a game of hide-and-seek with the charging beast, leaving behind streaks of afterimages. Lei Dong’s elusiveness tangled with the Fire Ox’s ferocity. It was only thanks to the entanglement caused by hundreds of fierce ghosts and the surrounding Netherworld Qi that Lei Dong could barely manage to avoid the charging beast intermittently.

In moments, this only served to further inflame the Fire Ox’s rage.

“Moo~” A deafening roar erupted. The Purgatory Fire Ox’s body blazed intensely, the flames coalescing into a single, dragon-like entity with bared fangs and claws, lunging at Lei Dong. Lei Dong’s feet continued their phantom running in the air as he sealed another hand sign, instantly forming a layer of chillingly transparent, icy shield around himself. Simultaneously, the surrounding Netherworld Qi also condensed, swirling out to meet the surging flames.

Boom!

The collision of the two forces unleashed a blast wave that made the very air crackle with thunderous concussive force. Although the Netherworld Great Art was one of the world's supreme disciplines, Lei Dong’s cultivation was still insufficient. In this direct clash, the Netherworld Qi only held for a few breaths before shattering. The remaining torrent of flame still retained considerable power as it swept toward Lei Dong.

Lei Dong’s evasive movements were fluid, like a specter soaring through the night sky. Tongues of fire constantly sought to consume him, but the Profound Yin Shield repelled them one by one. It was fortunate that Lei Dong had used his Netherworld Qi to momentarily block the attack; the flame’s power and momentum were largely dissipated, allowing the Profound Yin Shield to barely hold on. Moments later, the residual flames vanished. Lei Dong’s Profound Yin Shield shattered, and his hair had been scorched enough to curl slightly.

After unleashing that last spell, the Purgatory Fire Ox’s fiery aura instantly dimmed significantly, leaving it panting heavily. Its movements were no longer as swift and powerful when pursuing Lei Dong. It wasn’t just the beast; due to the intense evasion and combat, Lei Dong’s internal energy was also more than half depleted, leaving him struggling. However, thanks to his habitual use of the Heavenly Demon Transformation to aid his cultivation, he was far from the sensation of utter exhaustion and depletion that followed its full release, allowing him to persevere. At this point, he had just swallowed a Qi Replenishing Pill, and without realizing when it happened, his right hand was already clutching a high-grade spirit stone.

Although he couldn't quickly absorb the spiritual energy within the high-grade stone to replenish his reserves, merely holding the stone meant that its abundant and pure spiritual power would slowly seep into him without the need for forceful channeling, offering some small benefit during this prolonged war of attrition. If he had allowed the Ghost Guards, scattered nearby and concealed, to converge now, they could have easily slain the Fire Ox, which had expended most of its stamina and demonic energy. But Lei Dong remained elusive, continuing to lure and drain the Fire Ox’s strength. Originally, his evasions were extremely strenuous.

But now, it required significantly less effort than at the beginning. Lei Dong could now passively draw upon the spiritual energy from the high-grade spirit stone while maneuvering. His expression was solemn, and he remained silent.

Half an hour passed.

An hour later.

At this point, Lei Dong had slowly managed to restore his vital energy to seventy or eighty percent of its usual level. The Purgatory Fire Ox, worn down by the immense time and effort Lei Dong had invested, was finally on the verge of collapse, breathing heavily through its nostrils, its four hooves beginning to falter during its runs. If not for the sheer stubbornness inherent to the Fire Ox, it likely would have turned tail and fled long ago, unwilling to be entangled with this monstrous human any further.

Only then did Lei Dong summon the three Ghost Guards who had been lying in wait, ordering them to close in. As the Netherworld Ghost Qi surged, the three Ghost Guards revealed their terrifying, ferocious auras. Under their coordinated assault, the giant Fire Ox, now utterly exhausted and lacking strength, was carved into pieces within moments. Lei Dong retrieved a spare Soul Sealing Bead and sealed the lifelike, semi-transparent, shrunken spirit of the demonic beast—the Purgatory Fire Ox—into the bead.

As for the three Ghost Guards, they were brimming with excitement. They transformed into three clusters of terrifying, deeply dark mist, cold and chilling, and directly enveloped the corpse and flesh of the Fire Ox, beginning their consumption. Due to feeding on the flesh and blood, the three dark clouds gradually turned a gruesome scarlet, bloody and cruel. This was accompanied by the ghosts’ excited, piercing squeals—shrill and grating. Anyone unaware of the process might have been terrified into fainting on the spot.

Just then, a beam of light flashed and vanished. It left behind a single object, which Lei Dong retrieved. Upon inspection, his expression shifted to slight disappointment. This should have been the last guardian beast of the Black Tower, holding the possibility of containing a Heart Cleansing Fruit. But the piece of dark, crystalline ore in Lei Dong’s hand clearly had nothing to do with a Heart Cleansing Fruit.

“Come out now~” Having completed all this, Lei Dong stood with his hands clasped behind his back, watching his three Ghost Guards feed. He spoke the words in a cold, low voice.

But nothing happened.

Lei Dong sneered, a cruel smile spreading across his face: “Qi Feifei, don't force me. Don’t force me to kill you…”

“Hehehe…”

A cascade of clear, bell-like laughter rang out, and a streak of crimson light flashed past. Qi Feifei’s long, alluring figure materialized directly ten yards or so from Lei Dong. Although she was laughing, her fair, delicate face was now somewhat pale. She forced a smile. “Senior Brother Lei, please don’t be angry. Little sister wasn’t deliberately lurking nearby. I just wanted to see if Senior Brother Lei could slay this Purgatory Fire Ox alone. I truly didn't have any ill intentions…” As she spoke, however, she glanced nervously at the Ghost Guards, who were devouring the flesh and blood in an extremely nauseating manner, her face growing even whiter. It wasn't the gruesome scene of the ghosts feeding that frightened her, but the very strength of those Ghost Guards—or rather, the strength of Lei Dong himself.

“Hmph, Qi Feifei. I, Lei, am not some brainless fool who gets completely swept away by a few sweet words, losing all sense of direction.” Lei Dong snorted, glaring at her with palpable killing intent. “I know you’ve been waiting for an opportunity, but sadly, after waiting so long, you haven’t found one you were confident in…”

“Senior Brother Lei, you misunderstand me…” Qi Feifei’s face stiffened, and she began employing her most practiced seductive arts, her eyes overflowing with charm, her body exuding waves of delicate fragrance.

“Stubbornly refusing to yield, you court death!” Lei Dong’s face darkened with fury. The three Ghost Guards immediately ceased their feeding. They snapped into focus, their forms solidifying into a mass of scarlet, and charged toward Qi Feifei.