This F-Rank Bubble Mage Is Too OP!

The commotion from River's clash against the Dungeon Boss had been impossible to ignore.

The sound of the initial impact rolled through the E-Rank Dungeon like thunder, followed by a deep, gut-rattling rumble that seemed to vibrate through the stone underfoot. Then came the explosion—a deafening roar that split the stale air and sent flocks of swamp birds screaming into the sky.

It was enough to make every Hunter pause mid-swing, mid-step, mid-breath.

Rotlings, those decayed, disgusting creatures that skulked in the foggy muck, screeched and scattered as the tremor passed. A few Hunters instinctively raised their weapons, expecting an ambush, but when no immediate threat came, their attention shifted toward the direction of the blast.

"Was that… the boss's roar?" one muttered, lowering his spear.

No one answered. Instead, all eyes turned toward the far side of the swamp—the deep zone where only the bravest, or the most foolish, dared tread without preparation.

Without another word, boots splashed into the muck, weapons in hand, as Hunters abandoned their current fights and rushed toward the source. The sound of armor plates clinking, the squelch of swamp mud underfoot, and the distant crackle of flames guided them forward. Even the air had changed—gone was the stagnant, mildew-heavy smell, replaced with the faint tang of ozone, smoke, and something acrid, almost metallic.

The further they ran, the more visible the signs of devastation became. Trees, their roots knotted into the swamp, had been blasted apart, leaving jagged splinters jutting into the air like broken spears. Deep trenches had been carved into the earth, filled with steaming water and half-sunken Rotling corpses. In some places, the ground looked scorched black, as though lightning itself had raked across it.

By the time the Hunters arrived, the sight that greeted them made even the most seasoned among them pause.

The shallow pools that dotted the area were boiling, releasing clouds of vapor that drifted upward in twisting streams. Massive chunks of the terrain were gone entirely, as if something had ripped the land apart and hurled it into the distance.

The Dungeon Boss's lair, obvious if one has common sense, has clearly met a storm.

"This… they already fought the Dungeon Boss?" a Hunter finally spoke, disbelief heavy in his voice. His wide eyes reflected the steam and the glow from the moon, his face pale under the light.

"That seems like it," another replied, though his tone was wary, almost reluctant to believe it. "But… isn't it too early? The boss usually stays deep until we've cleared enough Rotlings. Why would anyone push it this soon?"

"Motherf*ckers must be eyeing the treasures," a third spat, his voice low and bitter. He jabbed the butt of his spear into the mud, sending up a small splash.

The murmurs spread quickly.

If the boss had already fallen, it meant the clock was ticking. Every Hunter knew the rules—once a Dungeon Boss was defeated, the dungeon's collapse was inevitable. Normally, there was a grace period of about an hour before the portal closed completely, but the timing wasn't always exact. Some dungeons lingered longer, others collapsed within minutes.

And when the portal vanished, there was no coming back. Anyone still inside would be trapped for the rest of their lives, wandering the corrupted pocket dimension until either the monsters or starvation claimed them.

The thought alone was enough to put an edge of panic into the air.

"Greedy bastards," one Hunter growled, scanning the clearing as though expecting the culprits to still be here. "They've just cut the dungeon's life short for everyone. I was halfway through farming Rotling hides!"

"Forget the hides," another snapped. "I had two cores left to get for my upgrade. Now I'll be lucky if I can even find another one with the remaining time."

Their complaints blended into one another—resentment, frustration, and a tinge of fear. Some Hunters turned to leave immediately, deciding to cut their losses and head for the portal before anything worse happened. Others lingered, scanning the devastation with wary curiosity.

One, a broad-shouldered man with a jagged scar down his cheek, crouched by the edge of one of the crater. He dipped his fingers into the steaming water and hissed at the heat before quickly pulling them back. His gaze swept the area, noting the depth of the blast marks.

"This wasn't just the boss," he muttered under his breath. "Whoever did this… their firepower is beyond E-Rank."

Nearby, another Hunter overheard him and frowned. "Are you saying a group of D-Rankers did this?"

The scarred man's expression darkened. "No. I'm saying someone much stronger is walking around in here."

That remark silenced a few of the louder complaints. The idea that a high-rank Hunter—or worse, something else entirely—was in the dungeon was unsettling.

But the clock was still ticking, and survival outweighed curiosity. Groups began to disperse, heading toward the portal at a brisk pace. The swamp echoed with the sound of hurried footsteps, splashes, and muttered curses as the Hunters tried to secure whatever loot they could before the dungeon collapsed.

Far above, the last traces of smoke from the battle drifted into the sky of the dungeon fading into nothing—yet the air remained heavy, as if the swamp itself knew it had witnessed something it wasn't meant to see.

As most Hunters hurried toward the glowing portal in the distance—some dragging loot, others limping from injuries—one last group finally stumbled into the devastated clearing.

They slowed to a halt at the edge of the battlefield, eyes scanning the carnage.

"What… the hell happened here?" Kayl muttered, planting the barrels of his twin gatling guns into the mud and leaning on them like a pair of heavy canes. His voice carried a mix of disbelief and grudging respect.

The rest of his team looked equally unsettled. One of their Physical Class Hunters carried an archer slung over his back, the man pale and grimacing, his two legs little more than a hastily bandaged stump. The injury was courtesy of the same strange opponent they'd all encountered earlier—the one wearing that bizarre toy mask.

Even now, after that fight, their bodies still ached. Potions had dulled the pain and sealed the worst of the wounds, but the deeper bruises, fractured ribs, and mana exhaustion lingered. Kayl knew it would be several more hours before they could return to peak form.

The group fanned out slightly, taking in the scene. Steam still rose from patches of swamp water, drifting like thin ghosts through the humid night air. Dead trees lay splintered in every direction, and chunks of blackened earth marked where something powerful had detonated.

"This…" Kayl's eyes narrowed as he studied the destruction. "This looks like a battlefield from D-rank Hunters. There's no way in hell an E-Rank could cause this much damage."

He was the most experienced among them, and his words carried weight. He'd seen the aftermath of A and B-Rank clashes, and while this wasn't quite at that scale, it was far beyond what any organized E-Rank team should have been capable of.

Normally, when E-Ranks decided to take on a Dungeon Boss, they did it with precision. Multiple groups would coordinate, holding the boss in one place, avoiding unnecessary destruction, and focusing on clean, efficient takedowns to minimize casualties.

This… was the opposite.

By the looks of it, the Dungeon Boss had been all over the swamp—charging, thrashing, dragging its attacker from one end of the clearing to the other. The battle's footprint was erratic, chaotic.

Kayl turned to their mage, a thin man in deep-blue robes who was adjusting his cracked spectacles. "What do you make of this?"

The mage didn't answer right away. Instead, he stepped forward and closed his eyes. His breathing slowed as he reached out with his senses, feeling for the faint traces of mana that still clung to the battlefield.

"The mana has already dispersed," he said finally, exhaling in frustration. "There's not much left for me to read."

He opened his eyes, gaze wandering to the nearest crater—an almost perfect circle, its edges glazed over like glass. "But those craters… If I had to guess, they were made with the same ability or Skill, repeated several times."

Kayl's brow furrowed. "A mage?"

"Yes," the mage replied with a slow nod. "Or someone with exceptionally precise mana control. Whatever ability they used was focused, contained… but devastating."

One of the other Hunters, still holding his side from a rib injury, gave a bitter laugh. "So, what, the boss got nuked by a hidden high-rank? That explains why the portal's going to shut soon. Great. Just great."

The archer being carried grunted. "If it's the same guy we ran into before, we should thank our luck we're still alive." His voice was hoarse, strained. "I feel like he didn't use his full strength at us… Not like this. If he had…" He trailed off with a grim shake of his head.

That earned a moment of silence among them. They'd all felt the gap in power during that earlier encounter, and now, seeing this… it only confirmed their suspicions. Whoever was responsible had been holding back before.

Kayl gave the swamp one last look, scanning for any sign of the victor. But there was nothing—no bodies, no movement. Whoever had done this had already vanished, leaving nothing but destruction in their wake.

"We shouldn't linger," the mage said quietly. "The portal's lifespan isn't fixed. This dungeon might close in thirty minutes, or ten. If we get caught when it collapses—"

"I know," Kayl cut him off. "Everyone, move. We're leaving."

They didn't need telling twice. The group fell into a brisk march, boots splashing through shallow pools and sucking free of sticky mud. Even Kayl, despite the weight of his weapons, picked up his pace.

As they crossed the swamp, the sounds of other Hunters still echoing in the distance grew fainter. The glow of the portal began to pulse brighter with each passing moment—a sign the dungeon's stability was weakening. The mist overhead thickened, curling low like it wanted to swallow them before they escaped.

The archer on his teammate's back glanced over his shoulder, eyes lingering on the ruined clearing. "Whoever it was," he murmured, more to himself than to the group, "they fought like they didn't care about the dungeon closing… or about anyone else stuck inside."

No one replied.

The only sound was the squelch of their boots and the faint, rhythmic hum of the portal growing louder ahead. In the back of all their minds was the same thought:

They'd just walked through the shadow of something far beyond their rank—and it had chosen to let them live.

But one of them had other thoughts.

Kayl's eyes glinted with revenge and killing intent.