The two young sisters wandered through the forest gathering wild plants.

They naturally knew how to distinguish what was edible from what was poisonous. It was a skill necessary for survival. Had they never learned it, there was no way they could have survived this long in the mountains.

Sweat dripped down the older sister’s face as she filled her basket with wild greens, edible mushrooms, and plump larvae dug from beneath the soil. They had ventured unusually deep into the forest today, and the harvest had been excellent.

So excellent, in fact, that neither of them realized how dark it had become.

“Unni, what’s that?”

Her younger sister tugged lightly at her sleeve.

The older sister already knew what was coming. At her little sister’s age, questions never stopped.

What’s this?

Why?

How does that work?

Whenever they left home, she constantly warned her to stay quiet.

It rarely worked.

“Shh. Don’t talk.”

She scolded her absentmindedly and lifted her head—

Then froze.

It was dark.

And the forest was trembling.

After spending so many years surviving in the mountains, the older sister had developed instincts as sharp as a wild animal’s.

And right now, every one of those instincts screamed that something terrible was approaching.

Slowly, she tilted her head toward the sky.

Dark clouds drifted overhead.

No—

Her eyes widened.

‘...!’

“Get down!”

She slammed her younger sister’s head downward and dragged her behind a rock.

A swarm of mamool flooded across the sky above them.

The creatures blotted out the heavens completely.

Only then did she realize her teeth were chattering uncontrollably.

The overwhelming demonic energy filling the air made her younger sister collapse foaming at the mouth. Terrified, the older sister pressed her entire body against the child to suppress her convulsions as much as possible.

So the mamool would not notice them.

Because of that, she never saw where the swarm was heading.

Toward the dungeon ruled by the newly famous hero—

Ian.

***

A white dwarf cast his fishing net into the sea.

It was his duty to ensure the demon tribe he served always enjoyed plentiful meals.

The white dwarves and black dwarves, both naturally skilled at maritime work, had adapted surprisingly well to life in this new world. They lived diligently and comfortably.

Whenever he delivered seafood offerings to the castle, he would see human slaves being whipped and could only click his tongue in disdain.

“Idiots.”

His race had made the correct choice.

That was why they now enjoyed peaceful lives.

Humming cheerfully to himself, the dwarf turned the wheel of his boat.

Today’s work was finished.

It was time to return to his warm home.

He carefully sorted the finest unblemished fish aside as tribute while cleaning the rest for himself. After removing the scales and bones, he sliced several pieces into sashimi and tossed them into his mouth.

It tasted heavenly.

“Kraaah.”

He took a long drink of alcohol and lazily narrowed his eyes.

‘Is the wind getting stronger?’

The weather had shown no signs of turning rough, yet the boat rocked strangely against the waves.

Still, the shore was nearby.

With decades of sailing experience behind him, the dwarf felt no concern.

“Let’s see... wind’s good, water’s good...”

CRACK!

The ocean suddenly convulsed.

Before the dwarf could even scream, an enormous wave swallowed the fishing boat whole.

The white dwarf vanished directly into the maw of a mamool.

The sea became violent in an instant.

Massive waves crashed against the shoreline in exploding foam.

And from within those waves emerged a colossal sea mammoth mamool, dragging itself onto land.

Its skin was pitch-black.

Its eyes glowed crimson.

Its tusks stretched all the way down to its chest.

A black dwarf repairing the wall of an inn spotted the creature and clicked his tongue irritably.

“Tsk, tsk. Get lost. Even demon lords visit this place. Do you think they’ll spare you if you make trouble here? You’d better—”

The black dwarf disappeared into the mamool’s mouth before he could finish speaking.

***

Deep beneath the sea—

The Underwater Kingdom.

BOOM!

“Your Majesty! Your Majesty!”

“What is it? Compose yourself! Where are your manners?”

“It must be urgent. Oh dear, you aren’t part of the palace staff. What happened?”

“...Ahem.”

“Oh my.”

The former mermaid princess—now Queen of the Underwater Kingdom—quickly straightened her posture after glancing at the chamberlain who had just scolded the visitor.

Then she spoke with forced dignity.

“Ahem. What is the matter?”

“Mamool...! A swarm of mamool is passing through!”

The merman who burst into the royal hall gasped desperately between words.

“A swarm of mamool? ...Passing through?”

The Mermaid Queen blinked in confusion before quietly whispering to her chamberlain.

“If they’re only passing by... isn’t that a good thing? Doesn’t that mean we don’t have to fight them?”

“Her Majesty’s judgment is wise. It means they have not discovered us. Did you truly run all the way here just to report something so trivial?”

The chamberlain’s voice sharpened with irritation.

The merman frantically flapped his fins.

“No! That’s not what I mean! The swarm is enormous! They’re devouring everything! Destroying everything in their path!” 𝕗𝐫𝐞𝕖𝕨𝐞𝗯𝚗𝕠𝘃𝐞𝚕.𝐜𝗼𝚖

“Mamool are savage creatures by nature. Is this your first time seeing them? You’re far too easily frightened. Someone bring this man warm tea and prepare a room for him. He clearly needs rest.”

The Mermaid Queen answered kindly.

A lesser ruler might have punished him for creating chaos in the royal court over nothing, but she was far gentler than her father had ever been.

Though the chamberlain looked displeased, he obeyed her command.

“Guards! Remove him immediately. He should be grateful for Her Majesty’s mercy. And find whoever allowed this fool into the palace and punish them at once—”

“No! No, listen to me! The mamool swarm is trampling everything!”

The merman flailed wildly, panic distorting his voice.

At last, the chamberlain lost patience.

“This lunatic—throw him out!”

“Wait.”

The Mermaid Queen raised a hand.

“Let him speak.”

The chamberlain reluctantly fell silent.

The merman clutched his head with both fins. His unfocused fish-like eyes made him appear half-mad with terror.

“The sea mamool swarm... they’re eating all the fish. They’re crawling onto land and devouring dwarves, humans, buildings—everything. Even the demon tribes’ slaves!”

“That’s impossible.”

The Queen’s expression stiffened.

A war between demon tribes?

If a large-scale conflict erupted nearby, the hidden Underwater Kingdom could be exposed.

Still, they were not entirely defenseless.

“Soldiers!”

The Mermaid Queen rose from her throne.

***

Deep within the darkness—

A swamp suddenly began to churn violently.

Bubbles rose to the surface, swelling larger and larger before bursting apart.

Then pitch-black sludge emerged from the depths.

It devoured everything in its path.

The swamp darkened until it resembled liquid ink.

Like an unwelcome visitor concealed by night, it crept silently forward in the same direction the mamool were gathering.

The living darkness consumed everything it touched, growing larger and stronger with every passing moment.

An elf standing watch—

Swallowed whole.

A beast with its fur standing on end—

Consumed instantly.

Silence followed.

.

.

.

“Huff—!”

Ian’s pupils widened as awareness returned.

The event cutscene had ended.

This was the beginning of Reverse Dungeon’s main event—

Infinite Dungeon Defense.

Keith gripped Ian firmly by the shoulder.

Keeping his head lowered, he asked quietly,

“Are you alright?”

“No.”

Ian was absolutely not alright.

“What should we do?”

Keith glanced toward the collapsed elf bleeding on the floor.

Above the elf’s head, Ian could see his name and loyalty meter.

His stomach twisted violently.

Ding!

There was one thing Ian understood with horrifying certainty.

If he gave them an order—

They would obey.

Even if it killed them.

Dungeon Defense had many important mechanics, but the foundation of the entire game was the management of loyalty and distrust.

If loyalty dropped too low, troops deserted.

If distrust rose too high, they disobeyed commands.

But during this battle, even the recently recruited elves had never broken formation.

Just like every defensive battle Ian had cleared before.

‘No. This is wrong.’

Ian’s expression darkened.

Did this dungeon possess enough strength to survive an Infinite Dungeon Defense?

‘No.’

He had played this game countless times.

His judgment came instantly.

But these people—

They would never run.

Ian had to give an order.

Anything.

If he failed to act, they would stay here and die with him.

“He acts like he’s the only one doing any ✪ Nоvеlіgһt ✪ (Official version) work.”

The bitter complaint of a coworker from the smoking area echoed in his ears.

“Who told you to work like this?!”

The furious voice of his superior followed immediately after.

Ian had never once said:

“It wasn’t me. It was the nepotism hire.”

Because he already knew nobody would listen anyway.

He had grown used to it.

Back then, it had only been miserable.

But now—

‘What the hell... what is this?’

Now it terrified him far more.

Because this time—

Everyone would listen.