The end of the research lab corridor was unusually dark and silent.
The fluorescent lights in this section had gone completely dark, and the water had grown deeper, reaching Siul’s waist.
“Be careful. The boss room is just ahead.”
Siul stopped walking and warned Zero.
In truth, Zero had already noticed it as well.
A half-crumpled iron door stood ahead of them, and an oppressively dense concentration of Mana seeped through from the other side.
An instinctive certainty washed over them that something powerful was waiting inside.
“Let’s get ready before we go in.”
Siul spoke with Zero in front of the boss room.
“The boss of this Dungeon is the King Slime. It’s a hundred times larger than an ordinary Slime, and the more you attack it, the more it splits its body apart and creates Slimes that it can use as minions.”
Along with the information Park Jung-gi had given him from the Dungeon manual, Siul explained their strategy.
“Trying to fight something like that head-on would be suicide. So we’re going to….”
Siul opened his Inventory.
“…use this.”
He took out a small metal device and placed it on his palm.
It was shaped like a white disc, with a green circuit pulsing at its center.
『 Monster Adhesive Bomb 』 ― A-Rank
Reacts to a monster’s Mana after attachment and explodes 10 seconds later.
Siul rolled the bomb around in his hand and gave a dry laugh.
“It’s a single-use item, but it costs one hundred million won.”
Zero had no idea what one hundred million meant and merely tilted its head.
“It’s expensive, but its power is guaranteed. One of these should be enough to finish off the King Slime.”
Zero stared at the bomb with sparkling eyes, fascinated by it.
“Your job is simple. There’ll be Slimes gathered around the King Slime. If they come after us, stop them with your fire magic like you did earlier.”
“Woof!”
“While you’re doing that, I’ll get close to the King Slime and attach this bomb.”
Siul emphasized the next part in particular.
“Once I attach the bomb, we have to get as far away as possible within ten seconds. Otherwise, we’ll get caught in the blast too.”
Thanks to his immortality Trait, Siul himself could afford to take reckless risks.
Zero could not.
“Don’t rush forward under any circumstances. You stay in the back and fight from there. Understood?”
“Woof!”
Zero flapped its wings once.
It meant that it was ready.
Siul nodded and stepped toward the boss room.
“Good. Let’s go.”
* * *
The boss room was an enormous space resembling the main laboratory of the facility.
Each wall towered high, seemingly designed to accommodate massive experimental equipment, and the ceiling stretched so far upward that it was difficult to make out.
It was the largest Dungeon boss room Siul had ever seen.
“Wow.”
An exclamation escaped him without thought.
But he was not admiring the scenery.
He was staring at the creature occupying the center of the laboratory.
The King Slime.
【Continuous Quest Generated!】
【Eliminate the Threat to Your Life】
Personally eliminate the obstacle threatening your life.
Obstacle Danger Level: 10
Success Reward: 3 Level-Up Points
“That thing is enormous….”
The manual’s description of it being a hundred times larger than an ordinary Slime had not been an exaggeration.
A gigantic mass of gel, swollen like a mountain, sat plastered across the center of the laboratory.
Its upper body rose toward the ceiling, while its lower half covered the floor.
Its sheer mass alone was overwhelming.
Siul instinctively took a step backward.
SQUELCH—.
“…?”
As Siul stood on guard, the King Slime’s belly suddenly churned.
Its body was so enormous that he could clearly see the movement.
‘What is it doing?’
The King Slime had been staring toward Siul ever since he entered the boss room.
Despite having discovered an enemy, it had made no attempt to enter a combat stance and simply continued churning its stomach.
There were not even any obvious minions nearby to charge in its place, making its relaxed behavior seem strangely unnatural.
Before long, however, Siul understood what it meant.
WHOOOOOSH!!
The King Slime’s abdomen split open, and water erupted from the opening like a mouth.
No.
Calling it an eruption was not enough.
It did not merely pour water out.
It discharged an entire flood.
It was enough to make Siul wonder whether this was what it felt like to face a tsunami head-on.
“Uh… uh…!”
For an instant, Siul’s thoughts stopped completely.
The enormous volume of water swallowed the laboratory in moments.
A violent impact struck Siul, and his vision disappeared at the same time.
Eighty percent of the boss room had been submerged.
“Ghk!”
The water was nearly seventy meters deep.
Siul’s body was caught in a whirlpool and dragged beneath the surface.
He desperately flailed his arms, but he had already lost all sense of direction.
The freezing water and crushing pressure gradually blurred his consciousness.
‘Ah….’
Unable to endure it any longer, Siul inhaled.
His lungs immediately filled with water.
Drowning.
Siul’s consciousness went completely dark.
* * *
THUMP!
A wave of heat spread from deep within his chest.
【Trait ‘Cannot Die Until Death’ activates.】
His ruptured lungs regenerated, and the water filling them was forced back out as his breathing returned.
“Hah!”
Siul’s eyes snapped open underwater.
‘I-I came back to life…!’
At that exact moment, something grabbed him from behind.
“…?!”
His body was forcefully pulled upward.
Something heavy tightened around his waist.
When he looked back, turquoise scales entered his vision.
Zero had stretched out its tail, wrapped it around Siul’s waist, and was desperately beating its wings.
SWOOSH! SWOOOOSH!
Zero fought its way upward through the water with everything it had.
Thanks to its efforts, the two of them barely managed to break through the surface.
“Pwah!”
Siul sucked in oxygen and gasped for breath.
Zero, however, did not stop flapping its wings.
It remained airborne through relentless wingbeats, holding Siul up so that he would not sink beneath the water again.
“Thanks, Zero…. You saved my life. Well, I did technically die once… but thanks anyway.”
Siul stroked the tail wrapped around his waist as he expressed his gratitude.
Instead of answering, Zero simply flapped its wings even harder.
“What the hell just happened….”
Siul looked down beneath his feet with a pale face.
A gigantic shadow swam through the flooded laboratory below.
The King Slime glided through the water at tremendous speed.
Almost as if it were proudly demonstrating how fast it could move in this environment.
‘I’m too scared to even get close to it.’
From the air, the boss room had become completely unrecognizable.
The floor was nowhere to be seen.
The laboratory had transformed into one enormous tank.
“Mr. Park’s briefing didn’t mention anything like this….”
Siul was confused for a moment before shaking his head.
‘Why am I surprised? If every pattern and variable were already known, this Dungeon would’ve been cleared by now.’
Having a completely unexpected variable emerge in a boss room was perhaps the most natural thing in the world.
It had been the same when he was trapped inside the sealed stone chamber with the Giant Golem, and again when he struggled against the Shaman Orc’s healing magic.
‘Whatever happens, figuring out how to overcome it is my job.’
Siul collected himself and looked beneath him again.
He watched the King Slime darting through the water, trying to read the pattern of its movements.
‘I can’t possibly move faster than that thing in an environment where I don’t even have solid ground. Most of my skills are difficult to use underwater too.’
Siul’s gaze naturally shifted toward Zero.
“Zero, can you pull me underwater like you did just now? I can’t even get close to that thing under my own power.”
“Woof!”
Zero answered without hesitation.
“Thanks. I can count on you.”
Siul smiled and stroked Zero’s head.
Then he opened his Inventory.
『 Monster Adhesive Bomb 』
“We attach this to it and immediately escape into the air. Got it?”
“Woof!”
“Good. We go in on three.”
Before diving, Siul drew one final deep breath.
“One, two….”
Zero extended its tail farther and wrapped it firmly around Siul’s waist.
“Three…!”
SPLASH!
The moment they plunged beneath the surface, Siul could feel the King Slime’s densely concentrated Mana against his skin.
Zero paid it no mind and charged straight ahead.
PLIP. PLIP-PLIP.
“…?”
In the distance, Siul saw part of the King Slime’s body break away.
The detached mass transformed into dozens of Slimes.
‘Damn it.’
Siul immediately understood what the King Slime intended.
‘It doesn’t even intend to let us reach it….’
His prediction was correct.
The Slimes that had received its command rushed forward all at once.
They moved through the water like bullets.
Seeing the translucent masses approaching from every direction, Zero quickly opened its mouth.
FWOOSH—!
Fire Breath erupted from its mouth, but the flames immediately died out underwater.
Zero’s pupils trembled in confusion.
At this rate, dozens of Slimes might seize them, hold them beneath the water, and kill them.
Then, amid a stream of rising bubbles, Siul’s voice rang out.
“Keep going!”
The dagger shot from Siul’s hand.
SWISH—!
Tracker’s Blade changed its trajectory according to Siul’s will, slicing through the approaching Slimes.
The severed Slimes immediately split into two and multiplied, but it still bought them a little time.
SWISH!
The blade returned to him.
Siul glanced at Zero with an expression that said he could continue stopping the Slimes the same way whenever necessary.
‘I’ll handle those things. You just don’t stop.’
His intent was conveyed through his gaze.
From that moment on, Zero stopped hesitating.
It fixed its eyes solely on the King Slime and beat its wings even more fiercely.
Siul used Tracker’s Blade to hold back the Slimes surging in from either side.
Slash.
Multiply.
Block.
Multiply again.
After that grueling cycle repeated again and again, Siul and Zero finally reached the King Slime.
SQUELCH—.
The enormous mass of gel writhed and expanded its body.
It intended to swallow Siul and Zero whole.
‘Even better.’
The corner of Siul’s mouth rose.
He hurled the bomb in his hand with all his strength.
SPLAT!
Even though he had thrown it roughly, the King Slime’s swollen body made it impossible to miss.
The instant the bomb attached, the green circuit at its center turned red.
It had reacted to the King Slime’s Mana.
“Zero!”
Siul shouted with the last of the air remaining in his lungs.
Only ten seconds.
They had to escape the area before then.
Zero clearly understood that as well and immediately changed direction.
Leaving the King Slime and the attached bomb behind, the two began fleeing with everything they had.
But at that moment, Siul’s and Zero’s eyes widened simultaneously.
“GURURURU!!”
Slimes filled the water in every direction.
There was no path back.
Of course there was not.
The ones Siul had cut apart on the way in.
The ones he had blocked.
The ones he had allowed to multiply without killing.
All of those consequences had accumulated, filling the enormous tank.
The translucent masses shoved against one another as they closed in on Siul and Zero.
‘Get through all of that and reach the surface in ten seconds?’
By any reasonable standard, it was impossible.
But they could not give up here.
Zero twisted its body.
Summoning every last bit of strength it possessed, it tore through the water at a frantic pace.
Its wings and tail moved together as it desperately swam upward.
“GURURURU!!”
The Slimes had no intention of simply letting them leave.
As if declaring that they would never allow them to escape, they viciously surged forward.
SWISH!
Tracker’s Blade spun through the water, carving through the Slimes.
Siul’s determination was no weaker.
He continued throwing the dagger until it felt as though his shoulder would come out of its socket.
Of course, the more he attacked, the more enemies there were.
Dozens of Slimes latched onto Siul’s body with every passing second.
Soon, he could no longer throw the dagger.
His body grew so heavy that even Zero’s frantic wingbeats became useless.
Then a bomb notification flashed at the edge of Siul’s vision.
『 1 Second Until Explosion. 』
“……!”
Siul hurriedly turned and pulled Zero into his arms.
He did not care that Slimes were clinging all over his body.
The baby dragon’s tiny body disappeared into Siul’s embrace.
And at that moment—
BOOOOOOM—!!
The Monster Adhesive Bomb exploded.