This F-Rank Bubble Mage Is Too OP!

River parked his bike beside a small convenience store not far from the dungeon area—a run-down factory nestled in the industrial outskirts south of Voulton City. From the outside, everything looked normal. The streets bustled with pedestrians, office workers, and delivery trucks. There wasn't a single trace of fear or anxiety in the air.

People chatted happily as they walked by, clutching coffee cups and breakfast in hand. Couples laughed, teenagers loitered near food stalls, and a few kids even played with a stray dog on the corner. It was as if a dangerous portal, filled with monsters, wasn't pulsating just a few blocks away. The mundane rhythm of daily life continued unbothered, untouched.

River took a moment to observe it all. The calmness in their faces. The trust in their steps.

Even the Hunters standing nearby didn't look tense. They were gathered in small groups near the dungeon entrance, chatting casually while checking their gear. Their uniforms and equipment varied in quality, showing the divide in rank and experience, but their expressions all carried the same thing—confidence. Shoulders squared, heads held high, they moved with the kind of pride that made it easy for the average civilian to believe in them.

Several Non-Hunters passed by and offered them warm smiles and cheerful encouragements.

"Good luck out there!"

"Clear it fast, alright?"

"You Hunters are amazing."

To the untrained eye, it looked like a parade of heroes.

River sighed quietly.

The dungeon was still active, its unstable mana leaking into the surroundings like a heavy mist only sensitive people like him could feel. It had not been closed. The danger was still very real. And yet, everyone acted like it was already taken care of.

But this was Voulton City—one of the leading hubs for Hunter traffic in the nation. With over twenty known Guild branches operating in and around the city, people had grown used to the appearance of low-level dungeons. Most considered F-rank to D-rank portals as minor threats at best. Annoyances rather than dangers.

It made sense. These dungeons popped up regularly, sometimes several in a single day. Most were closed within hours. If a Breakout did occur, it usually only resulted in a few casualties—sometimes none at all—before reinforcements from nearby guilds arrived.

River understood this logic. He had once shared that same belief. He too wouldn't have blinked twice walking past an E-Rank dungeon portal, even if it had been trembling with Rotlings just a few meters away. That kind of overconfidence had become second nature to Hunters and civilians alike. An illusion of security built on statistics, rather than reality.

But now, River saw things differently.

It wasn't about this dungeon. It wasn't even about today.

It was about the pattern—this quiet belief that someone else would always step in, that the system would always hold.

Because one day, it wouldn't.

And when that day came, their smiles would turn into screams.

River looked toward the dungeon gate, his gaze steady.

He wasn't here just to hunt monsters.

He was here to prepare for the storm no one saw coming.

But before the storm came, River had to face the ocean first—and raising his strength within this dungeon was only the first step.

He turned from the sidewalk and headed toward a nearby shop nestled between the convenience store and an old pharmacy. It was a small store, cluttered with toys, cheap masks, party favors, and other colorful knick-knacks. A place meant for children, not Hunters.

Yet it was exactly what River needed.

He scanned the shelves and picked out a white plastic mask—something clearly made for kids, shaped like a smiling cartoon superhero's face. It covered the upper half of his face, hiding his eyes and nose. A small button on the right side caught his attention. When pressed, the mask lit up with a spinning pattern of LED lights and played a cheesy, upbeat theme song.

Perfect.

He took it to the counter and paid with what little money he had left, not bothering to haggle. After slipping it on, he adjusted the strap at the back of his head. The mask looked ridiculous, but that was the point.

It was so ridiculous that no one would take him seriously—no one would recognize him, or care enough to look.

River didn't want attention. Not yet.

Fortunately, entering a dungeon didn't require a full identity check. All Hunters had to do was scan their Hunter Card at the entrance—a security measure designed for statistics and internal tracking. Only high-ranking officials could access deeper information, such as who entered what dungeon and when. But that kind of investigation took effort and reason.

And River? To everyone else, he was no one. Just some weirdo in a toy mask with a worthless skill.

He was counting on that.

With his mask on and his Hunter Card in his pocket, River walked toward the old factory that served as the dungeon's anchor point.

Several Hunters were already waiting at the front gate—some in proper gear, others in casual clothes. They glanced in his direction as he approached, curious, confused, or amused by the sight of a man in simple jogging pants and a glowing toy mask. A few smirked. Others shook their heads.

"Dead in five minutes," someone whispered under their breath.

River ignored them. He simply stood off to the side, arms folded, silent.

He wasn't here to make friends or prove a point.

He was here to grow.

And soon, that opportunity came.

A tall man in formal black attire—clearly part of the local Hunter Administration—stepped forward and unlocked the heavy iron gate to the factory grounds. The gate creaked open with a groan, revealing the cracked pavement and worn-down exterior of the building. The portal pulsed inside, visible through the shattered windows of the factory's central hall.

Hunters began to move.

River followed them quietly, keeping to the rear of the group. As they stepped through the crumbling threshold and entered the dungeon's boundary, the air shifted.

Mana.

It hung thick in the atmosphere like humidity before a thunderstorm.

At the center of the hall, embedded between broken steel beams and piles of rusted scrap, stood the portal.

It shimmered like a living wound in space. A dark void sat at its core—pitch black, like the center of a black hole—while blue arcs of energy spiraled around its edges in a slow, clockwise motion. It was beautiful in a terrifying way, both alien and magnetic. The ground around it vibrated softly, as if the portal itself was humming.

River could feel the disturbance in the air. Each breath tasted sharp, like the crackle of static just before lightning strikes.

He reached into his pocket and pulled out his Hunter Card.

One by one, the Hunters ahead of him scanned theirs and disappeared into the darkness, swallowed whole by the portal's churning energy.

When it was his turn, River didn't hesitate.

He scanned his card on a device.

The system beeped.

And with that, he stepped forward—into the abyss.