Iz said, "When exploring a dungeon, mastering illumination is essential."
"Repeat after me."
"Light that brightens the world, grant all things their colors."
He wasn't speaking the common tongue.
He was using the language of magic.
Along the way, Iz had filled Kanzaki Rei in on a great deal of magical theory. That was when Rei learned that incantations were performed in an entirely separate, specialized language—
[Primordial Tongue]
Only by chanting in this language could one resonate with mana and the elements, completing the release of a spell.
Only a very small number of people could cast without chanting.
Such individuals were either extraordinarily gifted in a specific category of magic, or had practiced a particular spell tens of thousands of times, refining it to absolute perfection.
Rei followed Iz's pronunciation and began to chant.
Rei: "Light that brightens the world, grant all things their colors."
Iz: "I beseech Jua for a spark of light to illuminate the path ahead."
Rei: "I beseech Jua for a spark of light to illuminate the path ahead."
…Huh.
This chant felt different from the others.
Beseeching Jua?
[Illumination]
Ding—
A bright sphere of light floated above Rei's head.
「Illumination (LV: 5) — Chant Time Reduced」
"Iz, in this spell's incantation…"
Boom!
Before Rei could finish his question, a burst of flame detonated beside his ear!
The searing heat forced him to instinctively condense ice-element mana around his body to block the blast—
Neutralizing the wave of heat.
He whipped his head around.
A bat, charred black, dropped to the ground.
Iz's expression had turned stern.
"Rei. We've already entered the dungeon."
"A dungeon is a place where monsters gather."
"In dangerous places, letting your guard down can cost you your life."
Rei swallowed and nodded.
"I understand, Master Iz."
This world had no status panel—no visible "HP," no "Vitality" value he could check at will.
Rei didn't know how sturdy his body truly was. From what he could tell, aside from the massive increase in mana, his physical constitution wasn't much different from when he had first transmigrated.
An ordinary human body.
If pierced by a blade, it would die.
His mindset had to change.
This was no longer a peaceful land without monsters. If he was killed here, he would truly die.
Rei took a deep breath.
Then refocused on the path ahead.
That was when he realized—
The countless dark shapes reflected on the rock walls weren't shadows cast by light.
They were bats.
Black bats, clinging upside down to the stone.
As they sensed his gaze, one after another, they unfurled their wings, revealing blood-red eyes.
"Shadow Bats. They dwell in dark caverns and blend completely into the shadows when motionless."
"One of the weakest Tier-One monsters. You'll find them in most cave-type dungeons."
"They attack by biting with sharp fangs and draining blood."
"They carry minor pathogens, but priests of the Church of Life can easily cure the resulting illness, so their disease factor is generally not considered in combat assessments."
Iz explained calmly beside him.
"Elite-tier Shadow Bats can attack with sonic waves. King-tier Shadow Bat Lords often serve as dungeon rulers."
As he spoke, Iz tossed over a staff.
Rei caught it.
It was the slender staff used during the Thunderstrike spell yesterday.
Bats, huh?
Fire-element attacks should be effective.
「Fireball (LV: 80)」
Whoosh!
With a light swing of the staff, five massive blazing fireballs formed around Rei.
Boom!
Boom boom boom boom boom!
In nearly an instant, the fireballs smashed into the rock walls.
Before the bats could even take flight, they were reduced to charcoal and fell.
「Fireball Proficiency EXP +1.2W」「Fireball Proficiency EXP +1.2W」「Fireball Proficiency EXP +1.5W」...
Fireball detonation!
Flame splash!
Explosion!
Chain explosions erupted in succession. The Shadow Bats lining the passage were annihilated before they could even initiate an attack.
None of them could withstand a single explosion from Fireball.
Killing monsters with spells granted proficiency!
And judging by this, the proficiency gain wasn't a one-time bonus.
After clearing this entire cluster of bats—
Rei gained 68W Fireball proficiency.
Fireball rose from LV: 80 to LV: 82.
A noticeable jump.
At his side, however, Iz let out a sigh.
"What a waste…"
"These bats were burned to charcoal."
"Otherwise, their corpses would've fetched a decent price."
So that was a factor too.
"Of course, it's normal for monster corpses to suffer damage in combat."
"Akase is not only a Level 5 Warrior—he's also a Level 3 Gatherer."
"He usually handles our resource collection. If you explore a dungeon without a Gatherer, your loot yield drops significantly."
So there were such profession divisions.
That made sense. A gathering profession was clearly valuable.
"Still, this trip is mainly to help you break through your mana limit."
"Less loot isn't a big issue."
Rei nodded.
They continued deeper.
At the same time, Rei casually practiced [Illumination].
「Illumination (LV: 30) — Shorter Chant, Extended Duration, Softer Light Source, Illuminates More Shadows, Dispels Darkness」
Illumination was different from other spells.
Even at Proficiency LV: 30, it still required chanting.
But now—
All he needed was to silently utter a single word:
"Light."
And the spell activated.
Compared to other magic, Illumination felt… special.
At LV: 30, it resembled a surgical lamp.
Within its coverage, there were no shadows at all.
As they pressed forward, only a few scattered bats appeared.
After killing them all, Rei gained another 500,000+ proficiency EXP.
This time, he used Wind Blades.
That way, the corpses remained.
Though sliced into pieces, at least they weren't ash.
Their value had increased—from zero to one.
Iz stored the monster remains in his spatial storage.
They moved further in.
Suddenly, the space opened up.
The cavern ceiling rose dramatically. Rei could see numerous protruding rocks jutting from the walls—
Like inverted spikes growing from the inside of an overturned bowl.
If Illumination had been lower level, those protrusions would've cast deep black shadows.
And right now—
Behind those protruding rocks stood jet-black panthers.
"Black panthers lurking in the shadows…"
Rei didn't need much imagination to understand what would've happened without high-level Illumination.
He likely would've been ambushed.
Rei raised his staff.
Swung.
「Ice Spike (LV: 90)」
Bang!
The black panther's eyes widened in disbelief.
A razor-sharp, high-speed rotating ice spike pierced through its abdomen.
The spike punched through its body and embedded into the rock wall, scattering blood and frost.
Seven ice spikes.
Seven different panthers, impaled.
Shh—!
In the very next instant, the remaining panthers launched themselves from the rock walls.
But now, their numbers were severely reduced.
Between initiative and reaction—
The balance of offense and defense had already shifted.
They were fast—
But not so fast that the eye couldn't track them.
And midair—
Rei raised his hand again.
Ice spikes formed instantly.
Suspended in the air with no footing—
They were nothing more than living targets.
Bang!
Five ice spikes shot forth, piercing through chests and skulls mid-leap.