Ronald began exploring below the surface of the water.

As the depth of his location continued to decrease, after two hundred meters, the surroundings could hardly be illuminated by sunlight, plunging into considerable darkness.

This is not the fairy tale world constructed by the "Labyrinth Picture Book."

Although Ronald could barely see his surroundings at the moment, in an environment that continued to darken, no matter how good his eyesight was, he wouldn't be able to rely on his eyes to observe underwater.

"In December 1831, I had the privilege as a naturalist, to board the royal warship 'Beagle', beginning a five-year global scientific expedition..."

Ronald immediately recited the spell from "On the Origin of Species."

Relying on the ability regarding biological modification, Ronald greatly enhanced his perception of water movement and sound.

Afterward, he was just like a fish truly living underwater.

Using this mode of observation, Ronald built a concrete understanding of his surroundings and then continued to accelerate his descent.

...

He kept descending, continuously approaching a depth of five hundred meters.

During that time, to adapt to the increasing water pressure, Ronald had to make corresponding changes to his body every once in a while.

By this point, he had already developed doubts in his mind.

According to the elder in the library's basement, outsiders coming to borrow the library's hidden books need to bring a pink crystal back there.

But such a deep-water area...

Even someone like him who holds the original canon feels strained, how could ordinary Casters accomplish it?

Perhaps there was a problem with his method?

Requiring outsiders to provide a pink crystal to borrow books might actually be a subtle form of transaction by the library!

According to the elder, perhaps some crystals were prepared in the city for outsiders to exchange using money or network connections. Anyone who wished to borrow books could obtain them through a corresponding transaction.

Instead of doing what Ronald was doing now.

Directly jumping into the sea and then deep diving into waters that ordinary people could absolutely never reach to collect crystals.

"Hmm?"

Ronald continued to imagine these things while simultaneously diving deeper.

Finally, close to a depth of six hundred meters.

He discovered, deep within the ocean below, a patch of indistinct radiance!

Though it was just newly discovered.

But with Ronald's experience, it was absolutely not the movement caused by one or two luminescent deep-sea fish.

There must be a large area of glowing objects at that location!

Indeed!

It is here!

Ronald immediately determined the situation.

Then, with a thought, he accelerated his descent and swam toward the glowing position.

The light source existing under the sea is unlike the sun in the sky, which can directly provide suitable lighting for nearly two hundred meters deep in the ocean.

So he descended only less than twenty meters further.

Ronald finally reached the sea bed where the luminous source was located.

Just as the underground administrator of the library said, there was indeed an extensive crystal forest here. The beautiful intermingling of blue and green light shot out from these crystals, thereby providing this bright spot in the sea.

...

Are these... all fluorite?

Ronald curiously examined the surroundings.

There are numerous naturally luminous stones, which in fact are minerals exhibiting fluorescent reactions. When exposed to sunlight, they indeed emit this blue-green glow.

And despite vision failing to discern the surroundings at more than six hundred meters underwater, sunlight still retained a faint brightness here, activating the fluorite nestled on the seabed.

"..."

Fwah—

With a sense of curiosity, Ronald landed at the seabed, his feet feeling the peculiar texture while stirring a slight drift of fine sands.

He then threaded through the labyrinth formed by this forest of fluorite.

While searching for the pink crystal needed by the library, he also began to have doubts.

A regular fluorite mine.

How could it give birth to such pink crystals capable of retaining light?

Given the substantial size of the Carpen Library's layers earlier, Ronald couldn't help but feel that the vicinity of this city conceals some secret.

If he had time to remain here and continue digging.

He might unearth something astonishing?

Slash—

Just then, a stream of water swept across Ronald's right arm.

With extremely sensitive touch, he immediately realized that there was something elongated swimming toward the left in that direction, approximately two meters long.

Could this be a type of deep-sea fish?

Ronald almost instinctively turned his head.

However, soon, he saw a surprising scene.

A deep-sea fish looking like a ribbonfish swam past his right front. By the glow provided by the fluorspar maze, Ronald clearly saw that between its scales was a layer of luminous fine gravel, beautifully otherworldly.

"..."

What kind of evolution could produce such a beautiful creature?

Facing a creature he'd never seen before, Ronald was momentarily stunned.

Without even thinking, he instinctively held onto a piece of fluorite beside him, letting himself gently swim forward, starting to observe the creature from behind at a distance.

Until drifting like this, floating in the water about two to three meters away.

Ronald's gaze pursued the creature, and inadvertently, as he glanced around the fluorite forest, he abruptly interrupted his thoughts of admiring the beautiful creature.

"This place seems not quite right..."

Ronald squinted and descended to a lower depth at a recessed area.

As his vision focused closely, he then discovered the specialness he had noticed earlier.

At the center of a substantial piece of fluorite below seemed to be a distinctly different glow shimmering, and the color was pink!

Is it this one?

Upon spotting the target of his journey, there was no room for hesitation for Ronald.

Casually retrieving the Sword of Saint Catherine from behind, he struck down hard on the piece of fluorite below.

Crack—

The sharpness bestowed by the Saint was certainly not something fluorite could withstand.

Ronald swiftly broke apart this large chunk of fluorite, subsequently finding a pink crystal within. At its core, a vivid point of light mirrored precisely the pink crystal displayed by the library elder!

Having confirmed his acquisition.

Ronald immediately pried this crystal from the fluorite and carefully placed it in his pocket.

But as Ronald re-slung the Sword of Saint Catherine onto his back.

About to begin his ascent to return to land.

Suddenly, a commotion burst beside him!

SWISH—

Amidst the tumultuous flow, Ronald swiftly turned his head.

And saw a giant claw composed entirely of glowing crystals suddenly extending from amid the crystals, then pincering fiercely toward him!