The method of sealing away the power of the abyss and using it by letting it trickle out little by little could grant tremendous destructive force, but its drawbacks were just as clear.
To begin with, the conditions for using it required one to have reached the 6th Circle, the entry level of a superhuman.
One had to be able to wrap oneself in mana to protect the interior of the body, and one’s mana control had to be exceptional enough to handle magic and the abyss at the same time.
On top of that, if one failed to regulate it even slightly, the abyss would devour the magic as it was being completed, causing the spell to fail and bringing an extreme backlash in its wake.
When he had first begun practicing it, the question of whether this was truly the right method had never stopped occurring to him.
But after he succeeded a few times in casting magic mixed with the abyss, much of his thinking changed.
‘This is… usable.’
Because even at a glance, its destructive power had become several times stronger.
And all he had done was add about a spoonful of that energy to a completed spell.
Of course, it looked rather ominous.
No, it was not merely ominous in appearance; it was ominous in reality as well.
After all, the abyss was being mixed into the magic.
He could not use this once he returned to the continent.
In the end, it was the same as releasing the power of the abyss into the world, and if there were people nearby who could not resist that power, they would inevitably be affected. In other words, he would likely have no chance to use it.
Unless he used it and then went through the extremely troublesome process of cleaning up afterward with divine power himself.
But that was ultimately a matter for when he returned to the continent.
‘Here, it’s a perfect technique beyond compare.’
At the end of the world, this was the perfect technique to raise the destructive power Hio needed most.
This was a place where the power of the abyss spread like oxygen, so there was no risk of running short.
Hio’s goal now was to escape this place and return to the continent as soon as possible.
To do that, he needed strength.
Strength powerful enough to leave Kreutzwald’s house, the only place that could be called a safe zone, and move around freely.
And in the end, to reach Tetradia, enter the Mage Tower in person, and escape.
That was the only method Kreutzwald had told him of for leaving for the continent, and it was what Hio aimed for.
The structure of this place called the end of the world was simple.
First, the place where Tetradia was located served as the center, and the farther one got from it, the fewer aberrations there were, and the lower the frequency with which the Watcher’s Eye appeared.
The closer one got to the center, the more numerous the aberrations became, their strength rose sharply, and the Watcher’s Eye floated there at all times.
‘Honestly, if Kreutzwald came with me, I feel like we could go right away.’
He glanced sidelong at his third master.
Kreutzwald was sitting in a creaking rocking chair, turning the pages of an old book he must have read hundreds of times over.
He wanted Hio to become capable of reaching Tetradia with his own strength.
He had said with his own mouth that he would help Hio grow stronger, but he would not help him escape.
Well, it might mean that he wanted Hio to grow that much stronger, that much faster, and protect the continent, but……
‘…It’s strange.’
In truth, there were far too many strange things about Kreutzwald.
If he could use the Magic Tower to go outside, why had he not left?
As for researching the power of the abyss, that research had already ended in half-success. The only ones who could use it were Kreutzwald and Hio, and it would be difficult to use on the continent in the first place.
If there were something else he needed to do, he spent all day doing nothing but reading books.
Nor was he lacking the strength to escape.
If his purpose was to raise Hio and protect the continent, then he could simply go out to the continent himself and protect it.
In short, Kreutzwald had no reason whatsoever to remain here.
And yet, he lived as though he had not the slightest intention of returning to the continent.
Hio had once asked about that question in a roundabout way, but no proper answer had come back.
All he had received was an answer that only deepened his doubts: that he would understand once he went to Tetradia.
“What are you lazing around for?”
“Ah, I was just preparing……”
To think he had noticed even that brief sidelong glance.
Before that ghostlike master, he had to be careful with every action, every thought.
In any case, what he had to do right now was become stronger.
To willingly accept Kreutzwald’s teachings.
“I am ready, Master.”
When he summoned Teordo before his eyes and respectfully called Kreutzwald, the old man rose with a clearing of his throat and approached.
As his doubts piled up, even that look of his—so excessively fond of respectful speech—seemed suspicious to no end.
Well… he did seem like he had simply been that kind of person from the beginning……
“Now that you can handle the power of the abyss quite convincingly, let us begin strengthening in earnest.”
Before he knew it, Kreutzwald had come to stand between Hio and Teordo.
“You will use the power of the abyss in place of death energy, but in some ways, the effect is even superior. However, what you must be careful of is that, if you make a mistake, the soul may be tainted by the abyss……”
And so, once again, the time of instruction flowed on.
* * *
After having the concept of strengthening drilled into him and learning its method, he began producing undead in earnest.
There were more than enough bodies needed for the process.
「Skill — ‘Death’s Sarcophagus’ is activating.」
Two hundred and fifty-five corpses stored in Death’s Sarcophagus.
They had originally been the bodies of humans or other living beings, but after being tainted by the abyss, they had become even more destructively twisted existences.
However, their corrupted souls had vanished, and only their strengthened bodies remained. Since their roots were human, compatibility should be good, and if he succeeded in producing them, it was certain they would be reborn as powerful undead with unfathomably high limits.
The problem was that he did not have strong souls befitting them.
“Kekeke… Souls, is it?”
Kreutzwald solved that problem for him.
“Do not worry about that.”
Exuding the scent of death befitting a necromancer, Kreutzwald picked up his staff for the first time in a while.
When he tapped it into the air, an enormous door, at least five meters tall, abruptly appeared.
A black wooden door rippling like a haze.
“It is a storehouse containing every soul I have collected throughout my life.”
Kreutzwald opened the door, and when Hio followed him inside, what he saw was—
「Trait — ‘Ghost Eyes’ is activating.」
A new world shining in all colors.
A still space where countless souls floated like stars.
As if hardened in place—no, as if sunk in sleep—countless souls remained motionless, each shining strongly in its own color.
As Hio wondered whether this was the effect of the eyes of the soul, whose spiritual power had risen, or whether all the souls Kreutzwald had gathered were unique—
“My disciple. You, too, can see souls.”
Kreutzwald’s voice sounded strangely excited.
“Those eyes, which even I only barely obtained after hundreds of years… you already had them.”
“…Yes. Well, it just happened somehow……”
“Kekeke… I see. Good. Very good.”
After bursting into laughter for a while, Kreutzwald walked ahead again.
“Since you can see them, this will be easier. The souls in this space are the souls of those who possessed high rank in life.”
“Mm……”
“Do not worry. There was not the slightest coercion involved, and every one of them was a soul with a heartrending story and much resentment, which I gathered in.”
“They are all asleep, right?”
“That is correct. What you must do is find souls that match well with the bodies stored in Death’s Sarcophagus and turn them into undead. Think only of that.”
“Souls that match well…… Is there any way to distinguish them?”
Hio asked while looking at a soul floating right beside his head as if on display, and Kreutzwald answered without turning back to look at him.
“Would there be such a convenient function as a method of distinction? You have no choice but to match them one by one.”
“…I suppose so.”
As expected, Kreutzwald could not see these brilliant colors emitted by the souls.
Just as Hio once had, he must see everything only in gray.
Which meant……
‘The color these souls possess is the ability they had in life, or the emotion they held at the very end.’
It was likely close to that.
If Purnel were here, he could have asked about this phenomenon……
For some reason, he did not want to tell Kreutzwald about this strange phenomenon.
If possible, he felt he must not reveal all the abilities he possessed.
That was what his instincts told him.
“I guess I have no choice but to keep repeating the work until I get lucky and stumble upon one.”
So he spoke with a deep sigh, as if frustrated, and only then did Kreutzwald turn back to look at Hio with a hearty laugh.
“That is the mindset a necromancer ought to have. Now you finally seem a bit more like a necromancer.”
“…Repeating the work until I stumble upon one?”
“Kekeke, yes. Whether it succeeds or fails, you have no choice but to insert the soul yourself and see, so it is a task that requires dreadful patience and repetition. I shall leave the door to the soul storehouse open. You should set your mind on making undead out of every body you possess.”
“All of them… And after I make them?”
“You will have to bind the undead you have made and strengthen them.”
“And once I finish all of that?”
“Then I shall teach you other 6th Circle magic.”
“…That’s still a long way off.”
He wanted to escape quickly, but the road ahead was long.
With that feeling filling him, Hio let out another deep sigh.
Kreutzwald patted Hio on the shoulder, passed by him, and headed back toward the entrance of the storehouse.
“The faster you learn, the faster you will be able to leave; if you are slow, then it will be that much later. So do your best.”
Leaving those words behind, Kreutzwald went outside.
Hio stared for a while at the place where he had disappeared, then turned his gaze back to the souls around him.
He was right.
For now, rather than thinking about this and that, he should focus only on becoming stronger.
‘First, I need to figure out what this color means……’
As for how to find out, well, was there any other way?
He had no choice but to match them one by one.
「Skill — ‘Death’s Sarcophagus’ is activating.」
More than two hundred sarcophagi appeared once again.
「Please select the undead to register in the skill — ‘Death’s Sarcophagus.’」
「Please select the undead you wish to withdraw.」
「List of undead registered in the skill — ‘Death’s Sarcophagus’」
「Slot 1 — Corrupted Flame Knight」
「Slot 2 — Corrupted Flame Knight」
「Slot 3 — Corrupted Flame Knight」
「Slot 4 — Corrupted Flame Knight」
…
「Slot 255 — Mass of Ancient Lightning Spirit」
With the list displayed before his eyes, he walked around the area until he discovered a soul as crimson as flame and stood beside it.
If this color was truly related to ability, then it would not take very long to create an army of 255 powerful undead.
Of course, since he did not want to show Kreutzwald the full extent of his ability, he would have to do some acting.
「Slot 1 — ‘Corrupted Flame Knight’ has been selected.」
The Corrupted Flame Knight was an Abyss monster that manipulated fire and had appeared on the 55th floor.
They had originally been Flame Knights, but after being tainted by the abyss, they had become even more destructive. Their armor had become their skin, growing so hard that even aura could not cut through it in a single stroke; their arms had increased to four; and instead of flames, they gave rise to the abyss as they charged. They were terrifyingly powerful foes.
However, their black souls had been annihilated by Hio’s “Celestial,” and only their bodies remained, stored in Death’s Sarcophagus.
“I hope they fit well……”
There were as many as 255 of these powerful things.
If they were combined with high-ranking souls befitting them, and on top of that steadily strengthened, just how powerful a legion would be created?
「‘Corrupted Flame Knight’ is being summoned.」
On his left was a crimson soul.
And before him was a pitch-black corpse with four arms and a height easily reaching two meters.
He stretched his hands toward both at once, raised his mana, and thought.
After receiving Kreutzwald’s teachings, just how strong would he become?
When would he be able to escape from the end of the world?
Would those outside truly be able to hold out until then?
‘…No, I decided to focus only on this for now.’
They would hold out well.
He had no choice but to believe that and grow stronger as quickly as possible.
Making that resolve once more, he called forth his mana, and the bright light it produced filled the inside of the soul storehouse.
Perhaps Hio had been thinking of things a little too easily.
The tremendous amount of knowledge he received from Kreutzwald.
The realm of the 6th Circle.
The time required to grow stronger after reaching the entry level of a superhuman.
And this place called the end of the world itself.
Perhaps he had thought too lightly of them.
Contrary to his belief that he would be able to escape soon, a year passed.
And in a world without Hio—
「Abyss — Failed to conquer the 62nd floor.」
「Abyss — Failed to conquer the 63rd floor.」
「Abyss — Failed to conquer the 66th floor.」
That time was far too painful.