This F-Rank Bubble Mage Is Too OP!

"I'm a mess," River muttered, wincing as he examined his torn clothes and battered body.

Burn marks streaked across his arms, and his side was discolored from where a shockwave had rattled him mid-flight. His Bubble Bombs—so reliable and powerful—came with a cost. Using them in such close proximity had scorched his skin and shaken his organs like a drum. Every breath felt like a knife grazing the inside of his ribs.

He touched his abdomen and flinched.

Something definitely shifted inside him.

But before he could fully assess the damage, a spike of pain lanced through his skull. White-hot, like a blade of lightning.

His vision doubled. A wave of nausea crashed over him.

Then—

He dropped to his knees, his face pale, eyes unfocused.

A guttural cough escaped his lips, and a mix of blood and bile splashed onto the black stone beneath him.

Mana Deprivation.

River gritted his teeth, trembling.

The burning sensation surged from his chest to his brain, like his very soul was being torched from within. His nerves screamed. His thoughts fractured. Even time seemed to blur, reduced to throbbing pulses of agony.

Every Hunter knew of it. Every Hunter feared it.

Mana Deprivation wasn't just about running dry. It was a full-system failure. The mana circuits inside the body—the unseen highways that carried a Hunter's energy—strained and spasmed when pushed too far. Some Hunters lost consciousness. Some went mad.

Some never woke up again.

River clawed at the platform, blood dripping from his mouth, breath ragged. He tried to stand, but his legs refused to answer. He collapsed again, barely catching himself on one trembling arm.

His vision flickered.

The Heartstone stood only a few feet away, pulsing softly like a heartbeat—calm, steady, as if mocking his suffering.

"Damn it…" River hissed, the words a dry whisper.

Summoning what strength he had left, he activated Mana Gathering.

His senses expanded. Invisible threads of mana curled toward him from every direction. They entered his body slowly, carefully—like streams of cool water trickling through cracked earth.

He inhaled shakily.

His MP gauge rose.

The pain didn't vanish, but the storm in his head began to fade. The spinning slowed. His thoughts began to align again.

River's Mana Control, honed through countless battles and silent years of mastery, worked overtime to re-thread his inner circuits and stabilize the flow of energy.

Still, the toll was heavy.

His bones ached. His muscles twitched uncontrollably. Just sitting upright required immense willpower.

Letting out a slow breath, he sat cross-legged, spine hunched, as if bowing to the still-lingering pain. He glanced around.

The chaotic void that once tried to crush him had changed.

The floating rocks, those massive orbiting boulders that spun like blades of a cosmic trap, had… stilled.

They hung in the air like statues, frozen in place.

Calm. Silent. Unmoving.

It was as if the Trial recognized his arrival—acknowledged his success—and offered a moment of respite.

River didn't trust it.

Sweat dripped from his chin. His chest rose and fell in shallow breaths.

River took a few minutes of rest, letting his pulse steady and the worst of the nausea fade. The pain lingered like a dull throb across his body, but it was manageable now—at least enough to move.

With a grunt, he pushed himself up on shaky legs. His limbs protested, his skin burned, and his chest ached with every breath. But he stood tall, gaze fixed on the center of the platform.

The Heartstone.

It floated just a few meters away, gently levitating above a carved stone pedestal that pulsed with the same quiet rhythm. The platform around it was cracked and scorched from the chaos earlier, but the Heartstone itself remained untouched, suspended in midair like a jewel enshrined by the void.

River stepped forward slowly, his legs heavy but steady.

The Trial's objective had been clear: reach the Heartstone. He had done that. He was here. Yet… there was no system notification, no sign of completion. Not even the usual voice that echoed at the start of each test.

That could only mean one thing.

He had to make contact.

River took another breath and lifted his hand, wincing as the movement sent a sharp jolt through his side. His fingers trembled as they reached toward the Heartstone, every step and motion a quiet act of defiance against his broken body.

As he neared, he got a better look at the Heartstone.

It was no ordinary crystal.

The Heartstone was the size of a clenched fist, shaped like an imperfect teardrop with jagged edges and swirling, vein-like patterns of glowing red and faint violet embedded inside. The surface pulsed softly, as if the crystal itself were breathing. Mana gathered around it like a current, flowing in slow, hypnotic waves.

It exuded warmth, yet it wasn't heat that River felt—it was resonance. The stone hummed with mana attuned perfectly to magic users, especially those with refined control.

River's fingertip brushed the surface.

The stone flared to life.

A surge of light enveloped him for a heartbeat—and then, the long-awaited notification echoed in his mind.

"Congratulations for passing the Second Trial!

You have demonstrated precision, control, and adaptability in a hostile dimension.

Trial Complete: Gravity Chaos - Trial of Control.

Reward: Grade A Item – The Heart of Mira"

Item Description: A rare craftable core born from condensed mana storms and refined dimensional energy.

When used in weapon or accessory crafting, it imbues the item with heightened mana resonance.

Increases Mana Control precision.

Increases maximum MP by 30%.

Slightly accelerates mana regeneration in high-pressure environments.

Especially effective when used in staves, rings, amulets, and mage-based accessories.

Note: The Heart of Mira can only be used once. Choose your craft wisely."

River's eyes widened as he took in the notification. His gaze shifted to the pulsing gem still glowing faintly under his fingers.

"Grade A…" he whispered. "That's almost unheard of in F-Rank Quests."

Most F-Rank Quests gave out low-tier rewards at best—maybe a C-Grade weapon, or some bonus EXP. But this?

This was a foundational treasure for a magic user. A core component that could define a mage's future strength for years to come.

Realization dawned on him.

This Quest had been disguised. No wonder the guy who first completed it refused to share details.

This wasn't a beginner's Quest. It was a hidden trial for the exceptional.

River stared at the Heartstone, now inert in his hand as it slowly turned into light and entered his Inventory. He will think about how he will craft it once he gets out of this dungeon.

His lips curled into a faint smile.

"I almost died for this…" he muttered, exhaling slowly, "…but it was worth it."

Then, just as he relaxed, the void around him began to shift again—the air bending, the ground trembling, and the sensation of space unraveling returned.

He was being pulled back out of the Second Trial.

Thinking about the reward he had just received, River grew even more excited for the final trial. If the first and second trials had already benefited him greatly, what more could the third offer?

Soon, his body disappeared—along with the chaotic space.