The waterfall roared behind them.
The moment Rio passed through the curtain of rushing water, the sounds of the outside world faded until only a muffled echo remained.
Cold droplets slid from her cloak as she stepped onto the narrow stone ledge hidden behind the waterfall.
The passage was exactly as she remembered.
Barely wide enough for two people to walk side by side, the ledge hugged the mountain wall before opening into a naturally formed tunnel.
The air immediately changed.
It became cooler.
Drier.
Ancient.
Rio looked over her shoulder.
"Everyone made it?"
Ryota climbed over the last section of the rope ladder before helping Ramos onto solid ground.
Kiraya lifted Silla over the edge with surprising ease while Hinabi steadied her from behind.
Sayanaki was the last to arrive.
Rather than climbing normally, she simply pushed off the cliffside once and landed silently atop the ledge.
She brushed a few droplets from her crimson hair.
"...Interesting entrance."
Rio smiled.
"It was designed that way."
She turned toward the darkness ahead.
The tunnel stretched deep into the mountain, illuminated only by faint blue crystals embedded naturally within the walls.
They produced just enough light to reveal the path without fully banishing the shadows.
Rio reached into her inventory.
A rolled parchment appeared in her hand.
With a flick of her wrist—
A translucent projection unfolded into the air.
Everyone instinctively stopped walking.
"...Whoa..."
Ramos stared upward.
An enormous map floated before them.
Unlike the rough sketches Rio had shown during their journey through Casakola Jungle, this one was far more detailed.
Every corridor.
Every chamber.
Every split in the tunnels.
Every hidden passage.
Hundreds of pathways twisted beneath the mountain like veins.
Silla slowly stepped closer.
"...This is..."
Rio nodded.
"The Aether Ruins."
Her finger traced the uppermost portion of the projection.
"The waterfall we just entered through..."
"...is here."
A tiny mark appeared near the very edge of the map.
Kiraya blinked.
"...That's tiny."
"It is."
Rio smiled.
"What we saw outside wasn't the mountain."
"It was only the outer ridge."
She moved her finger downward.
"This entire mountain..."
"...is hollow."
Silence followed.
Even Sayanaki raised an eyebrow.
Rio continued.
"The tunnel we're standing in now leads toward the heart of the mountain."
She traced a long winding route through the projected map.
"It'll eventually connect to the ancient ruins buried inside."
Massive halls appeared within the projection.
Broken temples.
Collapsed bridges.
Underground rivers.
Gigantic circular chambers.
Ramos swallowed.
"...Someone built all of this?"
Rio nodded.
"Long before players ever arrived."
"No one knows who."
Ryota slowly leaned towards Rio and slowly whispered
"Not even fifteen years later?"
And Rio nodded
She moved her finger again.
Past the ruins.
Past dozens of branching tunnels.
Toward a massive open chamber hidden deep within the mountain.
"This..."
"...is our destination."
The projection expanded.
Everyone gasped.
It wasn't another cave.
It was an enormous open basin carved naturally into the mountainside.
Sunlight poured through a gigantic opening overlooking the forests of Floor Three.
Waterfalls cascaded from above.
Natural terraces surrounded the area.
Ancient stone foundations covered the ground.
Trees had grown through forgotten ruins.
Kiraya's eyes widened.
"...It's beautiful..."
Hinabi stared in complete silence.
Rio smiled.
"This place never appears on any map."
"The system doesn't acknowledge it."
"But it's real."
She folded her arms.
"This..."
"...will become Crowned Era's headquarters."
Nobody spoke.
Even Sayanaki quietly looked at the projected image for several seconds.
Eventually—
She nodded once.
"...Good choice."
Rio smiled.
"I thought you'd approve."
She dismissed the image halfway before leaving only the tunnel network visible.
"Now."
"One important thing."
She pointed toward dozens of branching tunnels.
"The Aether Ruins weren't designed like a normal dungeon."
"They're a maze."
Every direction seemed identical.
Stone corridors twisted endlessly beneath the mountain.
Some looped back on themselves.
Others ended abruptly.
Several connected to completely different floors.
"If you don't know where you're going..."
"...you can wander here for days."
Ramos immediately looked horrified.
"...Days?"
Rio nodded.
She then whispered towards Ryota
"There are records in my previous life of players spending over a week trapped inside."
"They eventually died from monsters..."
"...or starvation."
Ryota was speechless until he accidentally screamed
"You're telling me if we get lost we're as good as dead?"
Silla instinctively grabbed the strap of her backpack.
"...That's terrifying."
Rio smiled reassuringly.
"Fortunately..."
"...I know the routes."
She tapped one glowing line.
"This is the safest path."
"We'll follow it exactly."
Silla finally let out the breath she'd been holding.
"...Thank goodness..."
"Otherwise we'd never make it."
Rio rolled up the projection.
"Stay close."
"No one wanders off."
Everyone nodded.
The group resumed walking.
Their footsteps echoed softly through the ancient passage.
The deeper they went...
The older everything became.
Strange symbols decorated the walls.
Some had almost completely eroded away.
Others still glowed faintly beneath centuries of dust.
Ryota quietly observed everything.
"...It's hard to believe nobody lives here."
Rio answered without turning around.
"They once did."
"What happened..."
"...is another mystery."
Minutes passed.
The tunnel gradually narrowed.
Rio continued leading the group at a steady pace.
Her eyes constantly scanned the walls.
The floor.
The ceiling.
Nothing escaped her attention.
Then—
Without warning—
She threw an arm backward.
"Silla."
"Stop."
The sudden command startled everyone.
Silla froze mid-step.
"H-Huh?"
Rio immediately grabbed the back of her shirt before she could unknowingly place her foot forward.
She slowly pulled her back.
"Don't move."
The atmosphere immediately became tense.
Ramos looked around frantically.
"W-What is it?"
Rio crouched.
She picked up a loose stone from the ground.
Without another word—
She tossed it ahead.
The pebble landed exactly where Silla had been about to step.
Click.
Everyone heard it.
A tiny mechanical sound.
The ancient floor suddenly split apart.
RUMBLE—
A massive section of stone collapsed inward.
Rows upon rows of rusted iron spikes shot upward from below.
The stone continued falling until it disappeared into darkness.
Several seconds later—
A distant impact echoed from somewhere far beneath the mountain.
Ramos' face turned completely white.
"..."
"...I almost..."
Hinabi slowly exhaled.
"...That would've killed her instantly."
Rio nodded.
"Yes."
She looked directly at Silla.
"Never walk without watching your footing."
"Even if I know the route..."
"...the Aether Ruins are filled with traps."
Her voice remained calm.
"But calm didn't make her warning any less chilling.
"The builders designed this place so that anyone who entered without preparation..."
"...would never leave alive."
Rio tightened her grip on Silla's wrist.
"Don't panic."
Before Silla could even respond, Rio bent her knees.
Then—
She leaped.
The distance between both sides of the collapsed stone floor was nearly four meters.
For an ordinary person, it would have been impossible.
For Rio—
It was effortless.
The wind rushed past them as the two sailed over the forest of rusted spikes below.
A heartbeat later, Rio landed soundlessly on the opposite side.
Her boots slid only a few inches across the weathered stone before she came to a complete stop.
She gently released Silla.
"We're across."
Silla blinked several times.
"I... I didn't even feel the landing."
Rio only smiled.
"Good."
Behind them—
Ryota crouched beside Ramos.
"Your turn."
Ramos immediately paled.
"W-Wait..."
"I don't like heights."
Ryota laughed.
"Neither do I."
"...That's not helping!"
Before Ramos could protest any further—
Ryota lifted him as though he weighed nothing.
"WAAAAAAIT—!!"
The scream echoed through the tunnel.
Ryota jumped.
The air rushed past them.
Ramos squeezed his eyes shut so tightly it almost hurt.
A second later—
They landed safely beside Rio.
Ramos slowly opened one eye.
"...I'm alive?"
Ryota grinned.
"Told you."
Ramos immediately dropped to his knees.
"I never want to do that again..."
Kiraya chuckled before placing a reassuring hand on his shoulder.
"You'll survive."
She then glanced toward the gap.
"My turn."
Unlike the others, Kiraya simply jumped across under her own strength.
Her landing shook the stone slightly.
Hinabi followed next, using a burst of mana beneath her feet to propel herself over the trap.
Finally—
Sayanaki.
She didn't even bother preparing.
One silent step—
One explosive movement—
She disappeared from one side of the pit and reappeared beside Rio as though the gap had never existed.
Ryota blinked.
"...You really like showing off."
Sayanaki ignored him.
Rio nodded with satisfaction.
"Everyone made it."
She turned back toward the tunnel.
"Let's keep moving."
The deeper they ventured into the mountain, the stranger the surroundings became.
The tunnel twisted constantly.
Every few minutes another passage branched away into darkness.
Some sloped downward.
Others climbed toward unseen caverns.
Many looked almost identical.
Ramos scratched his head.
"How do you even remember all of this?"
Rio answered without slowing.
"Practice."
"...And a lot of getting lost."
Everyone laughed quietly.
Even so—
Not once did Rio hesitate.
At every intersection she immediately chose a direction.
Left.
Right.
Straight.
Never once stopping to think.
It was as though she had walked these tunnels hundreds of times.
Eventually—
The cave widened dramatically.
Everyone stopped.
Before them stretched an enormous abyss.
A single weathered stone bridge crossed it.
Its width barely allowed two people to walk side by side.
There were no railings.
Only empty air on either side.
Far below—
Ruins.
An entire city lay hidden beneath the mountain.
Broken towers.
Collapsed walls.
Ancient streets swallowed by darkness.
Half-destroyed castles.
Gigantic statues covered in moss.
Silla slowly stepped toward the bridge.
"...There's..."
"...a kingdom down there."
Rio nodded.
"The Ruined Kingdom."
"It predates Evermount."
Kiraya stared silently at the abandoned city.
"So this mountain really is hollow..."
Rio smiled.
"I told you."
As everyone admired the breathtaking sight—
Rio suddenly raised a hand.
"Look carefully."
She pointed downward.
Near the center of the ruined city—
Something floated silently through the abandoned streets.
It resembled a knight carved entirely from black stone.
Fragments of broken armor orbited around its body while blue flames burned where its eyes should have been.
It carried an enormous stone halberd nearly twice its own height.
Above its head—
Its name glowed crimson.
Ruined Guard
The red letters alone made Hinabi's expression stiffen.
"...Red?"
Rio nodded.
"Far beyond our level."
"The system is warning us not to engage."
Fortunately—
The guardian continued drifting through the empty streets below.
It never looked upward.
It never sensed them.
Ramos swallowed hard.
"...Please tell me we're not fighting that."
Rio shook her head.
"Not today."
"We'll come back here later."
Her words made everyone breathe a sigh of relief.
They carefully crossed the bridge one after another.
Every step echoed across the enormous cavern.
No one dared speak above a whisper.
Only after reaching the opposite side did Rio finally continue.
"The hidden zone isn't much farther."
Hope immediately appeared on everyone's faces.
Even Ramos managed a smile.
"We're finally close?"
Rio nodded.
"Just around—"
She suddenly stopped.
Her expression changed instantly.
Serious.
Focused.
Ryota noticed immediately.
"...Rio?"
She slowly raised a fist, signaling everyone to halt.
Nobody moved.
Silence filled the tunnel.
Kiraya instinctively rested a hand on Lionheart's hilt.
Sayanaki's crimson eyes narrowed.
"What is it?"
Rio slowly leaned toward the tunnel entrance ahead.
Then she whispered.
"...We're not alone."
Everyone held their breath.
Rio pointed beyond the corner.
"There."
One by one, they carefully peeked around the edge of the stone wall.
Standing motionless before a massive circular doorway was another stone guardian.
Unlike the one patrolling the ruined kingdom below, this one remained completely still.
Its halberd rested against the ground.
Its glowing blue eyes faced directly toward the tunnel leading into the hidden area.
Above its head—
The same crimson letters floated ominously.
Ruined Guard
Rio slowly withdrew behind the wall.
Her voice was barely louder than a whisper.
"...That's the guardian protecting the entrance."
The hidden sanctuary...
...was only a few dozen meters away.
But between them and their destination stood a monster none of them were remotely strong enough to defeat.
Silence settled over the ancient corridor.
Not even the distant dripping of water seemed willing to disturb the oppressive atmosphere.
The Ruined Guard remained motionless before the massive stone doorway, standing like an eternal sentinel that had guarded the entrance for centuries.
Blue flames flickered inside its hollow eyes.
Its enormous halberd rested against the stone floor.
It had not noticed them.
Yet.
Rio slowly lowered herself behind the corner of the tunnel.
Everyone instinctively copied her movements.
No one spoke.
No one dared breathe too loudly.
After several seconds, Rio quietly turned around.
Her silver eyes immediately found two people.
"Ryota."
He looked up.
"Yeah?"
"Sayanaki."
The crimson-haired assassin lifted an eyebrow.
Rio smiled.
"You two are with me."
There wasn't even a second of hesitation.
Ryota nodded immediately.
"Got it."
Sayanaki simply crossed her arms.
"I figured."
Kiraya frowned.
"...What exactly are you planning?"
Rio didn't answer immediately.
Instead—
She crouched on the ground.
Using her finger, she brushed away the layer of dust covering the ancient stone floor.
Then she began drawing.
Everyone leaned closer.
A rough sketch of the corridor quickly appeared.
The entrance.
The Ruined Guard.
The surrounding walls.
Possible blind spots.
Distances.
Even the direction the halberd was currently facing.
Her fingers moved with astonishing speed.
Years of experience had transformed strategy into instinct.
Within less than a minute...
An entire battle plan lay before them.
Rio tapped the center of the drawing.
"The Ruined Guard stays here."
She circled its position.
"It doesn't patrol."
"It only reacts when something enters its detection range."
Ryota nodded while carefully memorizing every line.
Rio continued.
"This hallway is too narrow."
"We can't surround it."
"We can't outnumber it."
"And we definitely can't overpower it."
She looked at both of them.
"So..."
"...we're going to....."
Sayanaki narrowed her eyes.
"...You're serious?"
Rio nodded.
Her finger moved across the dirt again.
She drew three arrows.
One approached from the front.
Two split apart.
Another curved behind the guardian.
Finally—
One last line led directly toward the massive doorway.
Sayanaki stared for several seconds.
Then...
She blinked.
"...I wish this wasn't our only option."
Rio smiled.
"It will work..."
"Probably"
Ryota looked between the drawing and the guardian.
"...Actually..."
"...that might work."
Sayanaki looked at both of them.
"You two seriously think that's possible?"
Rio folded her arms.
"I don't know."
"That's why we're trying."
Sayanaki sighed.
"...That's not exactly reassuring."
Rio laughed quietly.
"No strategy survives first contact."
"We adapt."
She crouched again and added several more markings.
Small circles.
Mana flow.
Estimated movement.
Reaction timings.
She had clearly spent countless hours studying creatures like this in her previous life.
Ryota watched every movement carefully.
The more Rio explained...
The more the seemingly impossible plan slowly began making sense.
He finally looked up.
"It'll work."
Rio looked at him.
"You sound confident."
Ryota smiled.
"I trust you."
The words were simple.
Yet they carried absolute certainty.
Not blind faith.
Experience.
Since restarting Evermount...
Every impossible plan Rio had proposed had somehow succeeded.
Whether it was surviving Dragon's Peak...
Finding hidden bosses...
Discovering The World Legacy...
Escaping Epsilon Dawn...
Or reaching Floor Three ahead of every guild in the game.
Each time...
Rio had been right.
Ryota had stopped questioning her instincts long ago.
Sayanaki quietly watched the exchange.
Then she let out a small chuckle.
"...You two really are something."
Rio looked over.
"What?"
The assassin shrugged.
"I think you're both insane."
She glanced toward the enormous stone guardian standing silently at the end of the passage.
Then back toward Rio.
"...But."
A grin slowly spread across her face.
"I like insane."
Rio laughed.
"I'll take that as approval."
"You should."
Sayanaki pulled one of her daggers free.
"Because if this fails..."
"...we're probably dead."
Ryota scratched the back of his head.
"...When you put it like that..."
Rio stood up.
Dust fell from her knees as she looked toward the rest of the party.
Her expression became serious again.
"Kiraya."
The former Lionheart Knight immediately straightened.
"Yes?"
"You and Hinabi stay here."
Both women nodded.
Rio continued.
"No matter what happens."
"If something goes wrong..."
"...your priority isn't us."
Kiraya frowned.
"...What?"
Rio turned toward Ramos and Silla.
Her gaze softened.
"It's them."
Silla blinked.
"...Lady Rio?"
Rio nodded.
"They're NPCs."
"They can't log out."
"They can't respawn."
"If they die..."
"...they're gone."
The weight behind those words settled heavily over everyone.
Even Ramos, who usually panicked first, remained completely silent.
Rio looked back toward Kiraya.
"I don't care what happens to me."
"But those two..."
She pointed toward Ramos and Silla.
"...must survive."
Kiraya met Rio's eyes.
For a long moment...
Neither spoke.
Then—
Kiraya slowly placed a hand over her chest.
"...Understood."
"I swear on my sword."
"I won't let anything happen to them."
Hinabi stepped forward beside her.
"You have my word as well."
"If either of them is threatened..."
"...they'll have to get through me first."
Rio smiled.
"That's exactly why I'm leaving them with you."
She turned toward Ryota.
"Ready?"
He tightened his grip on his sword.
"...Always."
Rio then looked toward Sayanaki.
The assassin twirled one of her daggers before catching it in a reverse grip.
A confident smile appeared across her face.
"...Let's go do something incredibly stupid."
Rio couldn't help laughing.
"...That's the spirit."
Together—
The three of them silently disappeared into the darkness of the ancient corridor...
...toward the waiting Ruined Guard.