This F-Rank Bubble Mage Is Too OP!

Bubble Creation — the very first ability under the Bubblecrafter Skill.

At first glance, it was almost laughable.

An ability so simple and unimpressive that even children armed with nothing but soap, water, and a bit of enthusiasm could imitate it. All it did was allow the user to create bubbles out of thin air. Harmless, weightless, and ridiculously easy to pop. They floated aimlessly, glittering in the light, utterly lacking any offensive or defensive value.

In truth, the System wouldn't even consider it a real Skill. It was more of a party trick, a harmless novelty. The only redeeming quality was that, as long as the user had Mana Points, they could produce bubbles endlessly.

But even that was hardly worth bragging about.

After all, in a world where others could conjure blades of fire, summon bolts of lightning, or manipulate the earth itself, who would fear a man armed with… bubbles?

And yet, Bubble Creation was only the first of the many seemingly useless abilities under the Bubblecrafter Skill tree.

When River reached Level 20, he unlocked its second ability—one just as unimpressive at first glance.

Moisture Gathering.

On paper, it sounded absurdly mundane. It allowed the user to draw moisture from the air. The change was subtle, almost invisible to the untrained eye. The surrounding air would grow heavier, slightly damp, as if a faint mist had rolled in.

Its intended function was laughable—essentially adding "more water to the soap" of Bubble Creation. It was the kind of auxiliary skill that existed only to support the main one, like the handle of a broom—useful only because it was attached to something else. By itself, Moisture Gathering posed no threat. You couldn't stab anyone with humidity, and a damp breeze wasn't going to save you from an enraged beast.

It was the kind of ability you unlocked, tested once, and then promptly forgot existed.

River possessed something the majority lacked—exceptional Mana Control. Not just skill, but precision honed through countless battles and life-threatening encounters. In fact, among the Last Hunters, almost all of them call him Master for the way he manipulated Mana as naturally as breathing and because he teached them how to properly use their mana and Skills.

And in River's hands, even the most pitiful, laughably useless abilities could be turned into lethal weapons.

Moisture Gathering, for example, wasn't just about adding water for bigger bubbles. With the right Mana control, River could force the moisture to condense at a pinpoint, altering the density and thickness of his bubbles until they were far tougher than they appeared. What looked like a fragile sphere of soap could become a resilient orb capable of deflecting small projectiles—or worse, trapping enemies inside with suffocating efficiency.

The air itself became his arsenal, the humidity his ammunition.

Most would dismiss such abilities without a second thought. River smiled at that.

Because the moment an opponent underestimated him…

That was the moment they drowned in bubbles.

And right now, River was about to put his newly unlocked Moisture Gathering to the ultimate test—against the hulking abomination looming before him.

The Zombie Swamp Eater towered above the swamp, its malformed body oozing steaming black sludge that hissed on contact with the earth. The air reeked of decay and stagnant death, but River barely noticed. His focus was on the orbs drifting lazily around him—his bubbles.

Except… they weren't the same bubbles he'd been throwing around earlier.

A few moments ago, his creations had been delicate and translucent, shimmering faintly like soap films catching the light. Pretty, fragile, and—at least to the untrained eye—harmless. But now, the orbs were subtly different. They still reflected the swamp's dim light, but the sheen was darker, the surface faintly rippling as though something restless churned inside. The edges didn't waver as much in the air; they held their shape like a thin, glassy membrane.

To most observers, the change would be imperceptible unless they looked closely. But to River, the difference was night and day.

The reason was simple: Moisture Gathering.

From the moment each bubble appeared, River wove the second ability into its creation, drawing in water vapor from the air and even pulling trace moisture from the swamp's foul mist. Under his direction, that water merged seamlessly into the bubble's surface, thickening it without weighing it down.

The trick, however, was not just stuffing the bubble with moisture—it was in controlling the distribution of that moisture on a microscopic level.

With his Mana Control, River could compress the water molecules in the bubble's film, forcing them into an even, reinforced layer. This created a far stronger "skin" capable of withstanding impacts that would have burst a normal bubble instantly. The process was so efficient that he didn't have to reinforce each bubble manually hundreds of times. The strengthening happened as part of the creation itself.

And there was a second, more dangerous benefit.

Inside each bubble, River's old technique still churned—chaotic Mana entangled with compressed air. It was a volatile combination, like stuffing a balloon with high-pressure gas and unstable magical energy. Now, with the new water-reinforced shell, those destructive contents could be packed tighter, condensed to a point where the energy density skyrocketed.

The stronger shell acted like a pressure vessel, allowing him to push far more Mana and air inside without risking an early rupture. And the denser the contents, the more devastating the explosion upon release.

In short, Moisture Gathering had just turned his basic Bubble Creation from a fragile novelty into a compact, portable warhead.

And it was cheaper.

Because he no longer had to manually layer reinforcement over each orb, his Mana consumption dropped sharply. He could now produce more bubbles for the same cost—or fewer bubbles with far greater potency.

River's lips curved into a smile. The last time he'd been this eager to test an upgrade, the world had still been teetering on the brink of collapse.

"Let's see how you handle this," he murmured, and with a flick of his wrist, the bubbles shot forward.

His Mana propelled them like bullets, streaking through the mist toward the Swamp Eater's torso. The monster, sluggish from its half-rotten state, didn't even bother to dodge.

The first orb made contact.

BOOM!

A muffled yet vicious detonation ripped through the swamp. Chunks of blackened flesh tore away from the creature's side, and the tar-like sludge spraying from its wounds hissed louder as it splattered across the dead ground.

The Swamp Eater reeled back, its yellow eyes rolling toward River.

"Not bad," River said with a smirk. His steps quickened, his body leaning forward as he closed the distance.

Another volley of bubbles surged out around him—half of them aimed for the creature's legs, the rest fanning toward its upper body. The reinforced shells gave him enough time to guide their trajectories mid-flight, weaving them around incoming streams of boiling sludge.

The creature's response was fast for its size. Its chest convulsed, and with a wet pop, it spat a massive glob of molten tar directly at him.

River's senses—honed from years of battling horrors far worse than this—screamed a warning.

Without hesitation, he spun a bubble into existence directly in front of him, feeding moisture into it as fast as his Mana could handle. The projectile struck it dead-on. The bubble warped, its surface sizzling as the impact force rippled across it… and then it burst outward, dispersing the sludge harmlessly into a fine spray before it could hit him.

River ducked through the mist and was suddenly right at the Swamp Eater's feet. His D+ Grade Steel Dagger flashed in the dim light.

The blade was no masterpiece—it would never pierce a monster's hardened hide. But the Swamp Eater's body wasn't armor-plated; it was rotting meat. His weapon was more than enough if he aimed for the right spot.

He slashed upward, carving into the creature's knee joint.

A screech tore from the monster's throat. It lifted its foot instinctively, which was exactly what River wanted. He tossed a bubble underneath, reinforcing it heavily, and as the foot came back down—

BOOM!

The blast tore the lower part of its leg into shreds, black ichor gushing into the swamp water. The Swamp Eater staggered, half-collapsing as the ground trembled under its weight.

River didn't give it time to recover.

He darted up its side, using bursts of bubbles as stepping stones—creating them beneath his feet in rapid succession, moisture-hardened to support his weight for just a fraction of a second before popping. In moments, he was level with its head.

The monster roared again, spewing a foul stench that made his eyes water.

"Yeah, yeah, I remember your breath from last time," River muttered, gripping his dagger in reverse. He plunged it into the soft tissue just above the Swamp Eater's eye, twisting hard.

It screamed, thrashing violently. River leapt away, landing on a bubble mid-air before bouncing to the ground.

Dozens more orbs swirled into existence around him. Moisture condensed instantly, their surfaces gleaming like liquid glass.

The Swamp Eater turned toward him—injured, enraged, but not beaten.

River's smile widened.

"Round two," he said, and hurled every last bubble at once.

The swamp lit up with a chain of concussive blasts, each one louder than the last.

When the smoke cleared, the Dungeon Boss was still standing—barely. One arm hung useless, half its face gone, its chest a ragged mess of holes. But it was still alive.

River straightened, eyes narrowing. This was good. It meant he could keep testing.

And for the first time in a long while, he was actually having fun.