This Dungeon Grew Mushrooms

“Issue departure!” Ironjaw’s voice came from the deck above.

Smack!

Inside the cabin, Gero clapped his hands together. The fox eyes he usually kept half-lidded opened a little wider. “Then let’s begin.”

【Seven Sins: Sloth】

Standing beside Gero, Tanaka’s body suddenly swayed slightly. A blurred phantom peeled itself away from him.

At first, the phantom was transparent, like a reflection in water. Then color and texture rapidly filled it in—within a single breath, another Tanaka stepped forward.

This duplicate perfectly replicated Tanaka’s current physical appearance. Even the adventurer’s leather armor he wore, his tightly bound trousers, and the scuff marks on his boots were identical.

Only Tanaka’s underwater breathing amulet, which emitted a faint magical glow at his neck, the several magic rings on his fingers, and the potion bottles at his waist, were absent from the duplicate.

Without exchanging a word, the two Tanakas met each other’s gaze. The original smoothly removed those items and handed them over to the duplicate.

The entire process was fluid and practiced, as if he were merely switching a tool from one hand to the other.

Preparations complete, the duplicate pushed open the cabin door leading to the deck.

Ironjaw glanced at the Tanaka who emerged and noticed nothing amiss.

He gave this employer a brief nod, arranged for two snakefolk subordinates to specially protect him, and then, in one smooth motion, leapt into the still-murky seawater below.

The moment they entered the water, they were attacked by monsters again.

Although the area had just been cleared, this location was too close to the mist. In just a short span of time, new monsters had wandered over.

However, the mercenary group was no pushover. A snakefolk mage beside Ironjaw raised his hand, and the water flow turned into sharp blades, cutting down the two monsters before they could even get close.

In the dim depths of the sea, the entrance to the Tidal Sanctum was a massive gate embedded in the side of a colossal underwater ridge.

Yet the state of the dungeon entrance was strange. Two entirely different streams of magic power were colliding—one originating from inside the dungeon, the other coming from the direction of the mist.

The two currents of magic constantly crushed and clashed at the entrance. The spellcasters could clearly feel the oppressive pressure.

Every ten seconds or few minutes, somewhere near the entrance, the local magical confrontation would grow too intense and trigger a small-scale mana explosion.

After each explosion, a vacuum-like cavity would briefly appear in the seawater, followed immediately by a violent inrush of water, forming chaotic whirlpools that swept up seabed silt and debris.

This phenomenon had clearly only appeared after the mist passed through. For ordinary adventurers, it was already dangerous territory, and even mist monsters had died here in significant numbers.

Ironjaw raised an arm, signaling the entire team to halt in a relatively calm stretch of water outside the entrance. “Mages.”

Several staff-wielding mages stepped forward, guiding the surrounding chaotic magic to ensure that no mana explosion would occur inside the formation.

Taking advantage of this opening, the team quickly swam through the gate.

The moment they entered, they encountered even more monsters. One type, whose forearm bones had mutated into a pair of folding bone blades, cut an inattentive snakefolk cleanly in half in the very first exchange.

Although the ferocious monster was immediately focused down by the reacting snakefolk and killed under multiple water arrows and blades, Ironjaw’s expression darkened.

He knew this mission was dangerous, but losing a capable fighter the moment they stepped inside was a very bad omen.

“I’m inside,” Tanaka reported his current position from aboard the ship.

“Good. Stick with the group for now. When you pass the third room, move close to the wall on the left and activate the ring I gave you.”

Under Ironjaw’s command, the mercenary group cautiously cleared the monsters that emerged along the way while advancing down the main passage.

When the team passed through the third spacious but partially collapsed stone chamber, Tanaka—mixed into the middle of the formation—subtly edged closer to the left wall, which was covered in glowing moss and cracks, and injected a faint trace of magic into the brass ring on his left hand.

Click.

The duplicate pressed against the wall. The inner and outer layers of the structure suddenly rotated like a nimble hinged panel, instantly flipping him inside.

The entire process was shockingly fast. Before the surrounding snakefolk could even react, the employer’s figure vanished from their sight.

“Straight ahead, then turn left,” the foxman continued to guide Tanaka along this hidden interstitial passage.

Following Gero’s instructions, Tanaka advanced through the narrow corridor.

The third corner was right ahead. As he cautiously leaned half his body out—

A dark shadow surged out from the other side of the corner, carrying violent water currents!

“Gurgle!”

A fishman?!

The fishman’s trident stabbed straight for Tanaka’s throat, fast and vicious!

Almost purely on instinct, Tanaka grabbed the trident bare-handed, barely stopping the lethal strike from piercing him outright.

However, underwater, the fishman held an absolute advantage in strength. Inch by inch, the trident’s tip pressed closer to his throat.

Tanaka raised a single finger with great difficulty.

At his fingertip, white light flashed and vanished.

【Memory Deletion】

The fishman’s frenzied roar cut off abruptly, replaced by utter emptiness.

Its thrust froze mid-motion. Its entire body went slack, like a puppet with its strings cut, standing there blankly.

Only then did Tanaka have the time to draw his weapon. Before the fishman could recover, he pierced its brain.

The fishman’s body twitched a few times. The emptiness in its eyes was swiftly replaced by the gray pallor of death as it slowly sank to the bottom of the passage.

From the wound, in addition to blood, several white filaments drifted out.

Recalling that, during the brief stalemate, he had caught a glimpse of the opponent’s panel showing something like “Parasitized,” Tanaka backed away a few steps in disgust.

“Damn fox! There were fishmen lying in ambush here! Why didn’t you say so earlier? I almost died!” Tanaka complained angrily to Gero at his side only after the crisis on the duplicate’s end was resolved.

“The third corner, was it…” Gero offered no explanation. He simply nodded thoughtfully, then urged, “Continue forward.”

Not long after, Tanaka ran into yet another unexpected enemy.

Several half-demons—with a group of puji?!

And these puji looked wildly different from one another. Some were covered in rock armor with sharp conical spikes at the ends of their tentacles. Others had fish tails. They were completely different from the puji on his ship, which had been captured from the imperial forests.

Were these the rumored combat-capable puji?

But… this was way too absurd!

Pulling up the panel and seeing entries like 【Self-Destruct LV10】 and 【Sharpness LV10】, a chill shot up the back of Tanaka’s neck, his scalp going numb.

No communication. No warning.

The moment those half-demon soldiers spotted him, they launched an attack without hesitation, clearly identifying him as an enemy.

White light swept over him. The five half-demons locking onto him all had their eyes go unfocused at once, their attack motions freezing mid-action as they fell into a brief stupor.

However, the puji—already given their attack orders—were completely unaffected.

“Shit!”

Tanaka tried to retreat, but his speed underwater was far too slow.

Tentacles shot out. Before the duplicate could react further, it was pierced through in multiple places at once.

When the half-demons came back to their senses, the puji were busy pulling their tentacles back out of the wall, and in front of them, only several magical items were slowly sinking downward.

At the same time, anguished howls and furious complaints from Tanaka echoed inside the ship’s cabin.

…

Smack!

Gero clapped his hands together again. A small tuft of white fur fell to the floor.

Beside him stood Tanaka, in the midst of swapping magical equipment with his duplicate.

Gero took a deep breath.

Second round, begin!