In the midst of the untamed rainforest, I found myself immersed in a relentless forge of trials. Days blurred into one another, marked by the symphony of muscle strain, the rhythm of sweat tracing paths on my skin, and the elusive dance with sleep. With every stride, beasts fell to my blade, each encounter etching its mark upon me, shaping me in the crucible of battle.

Yet amidst the chaos, a transformation unfolded within me. It wasn't merely brute force that surged through my veins, but a refined strength, honed by the subtleties of combat. My senses, once dulled by the cacophony of the jungle, now danced to the whispers of the forest, anticipating the slightest tremor in the undergrowth. Each strike, each parry, became a stroke of mastery upon the canvas of conflict, guided by newfound control. I wasn't merely wielding a sword; I was orchestrating a symphony of steel and fury.

And so, as the curtain rose on this act of my journey, I stood poised to confront a formidable adversary. Though the path to -rank would have rendered the task simple, I refused to settle for the ordinary. No, I aimed to vanquish the beast at -rank, for it was this level of relative strength that I sought to attain - the strength necessary to face Lucifer himself in the future.

With narrowed eyes, I beheld the behemoth rising from the shadows, its massive form a testament to its power. The Obsidian Behemoth, a creature of darkness and might, loomed before me, a hybrid of bear and elephant, its obsidian hide gleaming in the faint light.

Infused with the elements of earth and wind, it possessed a formidable combination of mana. Yet, with a swift incantation, I conjured forth a lance of fire and launched it towards my adversary.

The beast, sensing the impending threat, attempted to muster a defence, but its reaction was too slow. Mana beasts, unlike humans, wielded magic in a manner unique to their kind. This beast primarily used mana reinforcement with limited long-range capabilities, which would allow my attacks to deal damage as long as I managed to land them.

As the lance exploded upon its skin, flames licking at its fur, the behemoth's eyes blazed with fury, a harbinger of the battle that lay ahead.

With a swift motion, I drew my sword, its silver blade gleaming in the dim light of the rainforest. With a whispered incantation, flames erupted along its length, enveloping it in a fiery aura.

This flame aura, a fusion of martial arts and mage techniques, crackled around me as I leaped into action, a surge of lightning propelling me forward.

The blade, now a dangerous beacon amidst the foliage, sliced through the air as I descended upon the beast.

A prickling sensation danced across my skin as the creature attempted to counter, its earth-reinforced hide deflecting the brunt of my fiery assault.

Undeterred, I countered with practiced precision, deflecting its headbutt with a well-timed swing of my sword. Using the momentum, I somersaulted behind the beast, the flames trailing in my wake.

With a deft manoeuver, I grazed its flank with my blade, the searing heat of the flames leaving their mark.

This was my strategy: to whittle away at the beast with relentless fire magic before delivering the final blow.

Once more, my honed instincts sprang into action, and I swiftly ducked beneath a gust of wind hurled by the beast.

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"Not just brute force," I mused, recognizing its long-range capabilities. In response, I conjured a wind blade of my own, strategically aimed to thwart any evasion.

Though the wind blade's impact was minimal, it served its purpose. With flames dancing at my fingertips, I closed the distance once more.

A rush of exhilaration coursed through me as the beast prepared to charge once more. Dodging at the eleventh hour, I utilized sparks of lightning and gusts of wind beneath my feet to evade its onslaught.

In a deft maneuver, I twisted my body, skimming past the beast's retaliatory strike with minimal harm.

As I engaged in battle, a sense of familiarity washed over me, as if I were rediscovering the intricacies of this body rather than learning anew.

Despite inheriting Arthur's memories upon transmigration, my body had initially felt unfamiliar, out of sync with my muscle memory. Yet, within a week, that disconnect had dissipated.

'Arthur was indeed unique,' I reflected, shrouding myself in a nimbus of water aura. The water element's flexibility would be crucial in a confrontation where my adversary possessed superior firepower.

With a decisive swing of my sword, I inflicted wounds upon the beast, strategically targeting vulnerable areas. When it lunged, I deftly parried with my water aura, maneuvering around its attacks.

The battle, though not overly challenging, hinted at the trials to come.

As the Obsidian Behemoth's aggression escalated, a primal fear gripped me. Its defensive stance shifted to a relentless offensive onslaught, its red eyes gleaming with madness.

With each charge, I relied on my water aura to mitigate the damage, though the beast's sheer power was daunting.

The breath was knocked out of my lungs as I was hit by the reduced sheer power of the beast's attack.

Gasping for breath, I felt the force of the beast's attack knocking me back, a grimace of pain escaping my lips.

"Annoying," I grunted, bracing myself for the next onslaught.

Recognizing my limitations in mana output compared to the raging behemoth, I knew I had to fight strategically.

Embers cascaded from my hands, setting the grass around me ablaze. This was why I had been moving constantly during the battle - to prepare for this moment.

As flames licked the air, my intention was clear: to envelop the surroundings in smoke. While the fire itself wouldn't harm a 5-star beast, the smoke would serve a crucial purpose.

Unlike humans, these creatures lacked intelligence, sparing me the fear of being outsmarted. The smoke would not only obscure our sight but also disrupt mana senses, fueled by the mana within the flames.

Though my mastery of mana wasn't sufficient to conjure destructive flames, the mana-infused particles within would confound the beast's senses, especially in its frenzied state of mind.

Despite the beast's abundance of mana, tracking it through the smoke proved easier for me, relying more on tremors in the ground and other indicators than on mana senses.

Continuing the battle, I launched spells from a distance, biding my time for the perfect opportunity to unleash God Flash and bring the confrontation to an end.

Employing 2-circle spells to divert the beast's attention, I seized openings to inflict substantial damage with stronger attacks.

With each strike, I whittled away at the beast's strength until it was ripe for the final blow.

[God Flash]

The lightning-infused sword strike drained the creature of its remaining stamina and mana reserves, leaving it vulnerable and defeated.

"You fought well," I acknowledged solemnly as the beast lay defeated before me, its eyes aflame with fury. With a cold resolve, I ended its suffering with a swift thrust of my sword.

After ensuring the battle's conclusion, I stored the beast's corpse in my spatial ring and retrieved the mana core—a 5-star prize.

With this, my journey to -rank was assured.

After a brief respite to replenish my energy and restore my mana core, I settled into a lotus position, focusing on the task at hand: absorbing mana from the core.

Drawing mana from the core proved far simpler than from the ambient atmosphere. The mana within the core was already purified by the beast, with a higher density that facilitated the process.

While I still needed to purify the mana once again, it was a much smoother endeavor compared to purifying atmospheric mana.

With each intake, I experienced familiar sensations of pain and strain, the price of advancing my power. Yet, with determination, I absorbed, purified, and integrated the mana into my core, repeating the process until my core shimmered with newfound purity.

As I ascended to -rank, a ripple of mana emanated from my being, subtly altering the environment around me.

With this achievement, I stood on par with Jin.