The next morning, I stood on the city balcony.
In my hand was a bottle of wine.
Using my finger, I pried out the cork and took a swig.
The wine that entered my mouth splashed and spilled out.
My jaw, vertebrae, and ribs were drenched without mercy, and the robe I wore became stained.
At the unique discomfort, I groaned.
"As I thought, eating and drinking is impossible..."
I possessed sight, hearing, and touch, but lacked taste and smell.
With only a skeleton for a body, what mechanism was I using to perceive these things?
The ability to produce voice was also unfathomable.
The ecology of the undead was not well understood.
Having completed my little experiment, I shifted my awareness to what lay below.
Countless undead swarmed there.
They were the people of the Royal Capital, now transformed into ghouls.
Most had died from exposure to miasma.
I had borrowed their corpses.
Those in an advanced state of decay must have been buried.
They had risen due to the influence of my miasma.
Not a few were in forms that should be called skeletons.
The undead huddled together in a cramped mass.
The overflow could not be contained within the castle grounds, spilling out into the lower town.
The majority of the undead not present here were patrolling the outer perimeter of the Royal Capital.
I had ensured they would be detectable to me if anything occurred.
(With this, the preliminary preparations are complete.)
I gazed out from the balcony over the cityscape of the Royal Capital.
An oppressive, gloomy atmosphere pervaded every corner.
The dense miasma-fog also spread, creating an environment that repelled the living.
Now, it truly resembled the Valley of the Dead.
The thought that all of this had been executed by my hand gave me much to contemplate.
However, I did not harbor a single shred of regret.
My decade-long revenge was complete.
It had progressed smoother than I had expected.
Of course, this was merely the prologue.
The real work began now.
My next objective was true world peace.
It was an abstract expression, but I had determined the concrete steps to achieve it.
Through the suffering and struggle in the Valley of the Dead, I had made one discovery.
As long as an evil exists in the world, humanity will unite.
For a fleeting moment, peace is constructed.
Prioritizing humanity's survival, they refrain from large-scale conflict.
It was the former Demon King who bore the world's evil.
Regardless of his ideology or purpose, it is a fact he prevented conflicts between nations.
Everyone did their utmost to slay the Demon King.
There, a solidarity transcending borders existed.
The ones who shattered that distorted equilibrium were none other than ourselves.
In the aftermath of a desperate battle, we slew the Demon King.
Of course, we did it to save the world.
The people also wished for the Demon King's death.
But reality is merciless.
Having come full circle, it has led to this situation.
The hero was executed, the sage became an undead, and the royal capital became a land overrun with undead.
As an ending to a heroic saga, it is perhaps too gruesome a development.
The notion that slaying a great evil would bring peace was a fundamental mistake from the very beginning.
What awaits beyond is conflict among humans.
The curtain rises on ugly wars where nations slaughter each other.
The disappearance of the Demon King as a deterrent is likely the greatest factor.
Once a common enemy is gone, people readily turn blades against their neighbors.
My execution, and that of the other, could be seen as part of that very pattern.
Though I am unaware of the current state of world affairs, similar tragedies are surely repeating.
Such a world is undesirable.
Far from peace, it stands at the opposite pole.
True world peace is achieved only through the reign of an indomitable evil.
That is, I become the Demon Lord and continue to instill terror in the nations of the world.
Always give them the premonition of ruin, making it unthinkable for humans to fight amongst themselves.
If so, people will naturally unite as one.
They will join hands to kill me.
Of course, I have no intention of actually bringing about the world's demise.
But I must not let them catch on to that.
I must never be defeated by anyone.
I must forever continue to threaten humanity.
That is the duty befalling whoever has slain the Demon Lord, that necessary evil.
It was a role only I could fulfill.
(And for that, I must prepare...)
If I call myself the Demon Lord, I must establish a suitable foundation.
First, I desire subordinates.
I have plenty of numbers, so what I seek are subordinates with high individual combat strength.
Currently, I possess the authority of the Valley of the Dead.
It is a superior ability of necromancy.
I intend to synthesize the collected undead into one powerful entity.
During the fall of the Royal Capital, I tried it several times, so I have grasped the method.
There are advantages to producing strong subordinates.
In addition to strengthening one's fighting forces, they can serve as insurance against the worst-case scenario.
As long as my subordinate undead exist, I will not be destroyed.
This is because it is possible to resurrect from any surviving individual.
In other words, it is equivalent to the number of my lives.
Given this trait, it is not a bad idea to keep a sturdy one on hand.
This alone can reduce the risk of my destruction.
I must not be slain.
To avoid repeating the tragedies humans inflict upon one another, enhancing my immortality was an urgent necessity.
"I will become the next Demon King."
Having solidified my resolve once more, I directed my awareness toward the undead.
I swept my raised arm in a horizontal line, activating my authority.
Immediately, the undead were engulfed in purple flames.
The purple flames spread, growing until they covered everything in sight.
Screams of resentment rose from the ground below.
The souls of the dead were suffering.
The miasma swirling through the atmosphere grew thicker.
I could feel the land being tainted, right through my skin.
The purple flames that had enveloped the undead below eventually gathered together, forming a single shape.
In the end, they vanished, leaving behind only white smoke.
The undead that should have been scattered across the ground were gone, completely incinerated without a trace.
In their place stood a singular, bony aberration.
"So that's the result of the synthesis."
I leaned forward, fixated on the monstrous form.
It stood as tall as an ogre, its base skeleton humanoid in shape.
Three pairs of secondary arms jutted from around its ribcage.
Its head was that of a bovine skull, crowned with impressive horns.
In its empty eye sockets, crimson flames flickered.
It was draped in a dense miasma that clung to it like a robe.
Its appearance and overwhelming presence alone made one thing clear.
This was an undead of immense power.
(Is it the apex of the skeleton type?)
Judging from its vast magical reserves, it likely possessed characteristics of the lich lineage.
Without exaggeration, it would rival the demon king I had slain in the past.
I hadn't expected such an individual to manifest.
Even with the massive number of undead it had consumed, this was clearly beyond any logical limit.
Had all the various factors simply aligned perfectly?
While I was lost in analysis, the bull-headed undead, which had been perfectly still, raised its head to look at me.
The flicker in its twin orbs of crimson flame ceased.
"It was you who gave birth to me?"
It was a voice pregnant with hatred.
It possessed a clear sense of self.
Moreover, it seemed my dominion didn't reach it.
Still, the fact that conversation was possible was significant.
If communication could be achieved, perhaps things could proceed peacefully.
"Indeed, it is I, but—"
"Nuungh!"
As if to cut off my words, the minotaur thrust out one arm.
From it, a bolt of black lightning was unleashed.
The lightning flew in a straight line toward me.
(Conversation is impossible. The opponent is berserking.)
I leapt from the balcony.
The black lightning bent at an unnatural angle, homing in on me with precision.
A tracking function? Or the caster was controlling it at will.
I fired a bullet of water from my hand, clashing with the lightning to nullify it.
I then created a magic field in mid-air to cushion my landing.
I maintained a position where I could look down upon the minotaur.
"Fuhahahaha, not bad at all! As expected of one who created me!"
The minotaur transformed the miasma wreathing its body into wings.
Beating them, it soared into the sky and rained down black flames from above.
The lightning from earlier was the same—it's mainly miasma.
This minotaur undead seems to be highly skilled at wielding miasma.
In terms of practical application, I wouldn't stand a chance.
(But I don't feel like losing)
I pushed back with a magical wind.
The black flames held for only an instant before being driven back by the gale.
They reversed course and struck the minotaur head-on.
"GUOOOOOOOHH!"
The minotaur, drenched in black flames, let out a deafening roar.
Its skeletal body was slightly scorched.
However, the wounds were far from fatal.
Its durability was equally formidable.
"Behold... my true power!"
The minotaur thrust both hands toward me and unleashed a rapid volley of black lightning.
The density was like a torrential downpour.
Each bolt carried destructive force equivalent to high-tier magic.
It could easily annihilate an army of tens of thousands.
I deployed multiple layers of magical barriers.
I prepared a hundred of them—translucent, dome-shaped shields.
Moments later, the rain of lightning bolts crashed into the barriers.
Sparks and explosions erupted.
Cracks ran through the ward, fracturing one after another.
The shockwave of destruction reached the castle behind, shearing away walls and spires.
The magical offense and defense ended in an instant.
My ward was roughly half-intact; only the outer layer had been shattered.
Of course, I myself sustained no damage whatsoever.
(A spell of even this magnitude can be blocked...)
Surveying the utterly devastated terrain around me, I felt a genuine admiration.
That was a good verification.
Even in life, I possessed a vast amount of magic power for a human.
However, even so, there were limits dictated by race.
To combat demonkind, I had employed all manner of stratagems in those days.
It was only by layering upon those foundations an immense amount of refinement that I finally came to be called a Sage.
In my current state, I am strong without such petty tricks.
In the singular realm of magic, I would likely brook no comparison.
Truly, the boon of the Valley of the Dead was immense.
"What... is this...?"
The bull-headed creature was in shock.
The rain of lightning strikes must have been a full-force attack.
To have withstood it unscathed would naturally leave one frozen in disbelief.
Meanwhile, I reshaped the remaining barriers into dozens of spears. Adjusting their points, I aimed them at the minotaur.
"Just stay down, for a moment."
As I moved my fingers, the spears fired in rapid succession. Their speed, leaving sound behind, forced the minotaur into a defensive stance.
Instantly, a miasma unfurled like a wall. The launched spears collided with this barrier of corruption. Black mist sprayed from each point of impact. Wave after wave of spears slammed into it, eroding the wall.
"Is this all you can do?!"
The minotaur's shriek echoed. It was desperately enduring the spear barrage. Of course, that was merely buying time. I allocated my awareness to the waiting spears and fired them all at once.
The miasma wall shattered effortlessly, and the piercing spears struck the minotaur's torso.
"Graaagh...!"
The minotaur plummeted. With a gaping hole torn through its body, it once again spread wings of miasma. It was trying to regain control and avoid hitting the ground.
"Not happening."
I severed the wings with a blade of wind.
The minotaur crashed headfirst into the ground.
It rolled through a billowing cloud of dust from the impact.
"Grrgh... you... damn you..."
The minotaur groaned as it pushed itself back to its feet.
The missing parts had been replaced by miasma.
The ability to keep moving even with fatal wounds was likely the innate immortality of the undead.
"Would you listen to me now? I don't want to fight."
"GRAAAARGH!"
The moment I touched down on the ground, the minotaur lunged at me like a beast.
All eight arms gripped weapons forged from miasma and magic.
They attacked in swift, unpredictable patterns.
—I can see it.
I conjured a sword with magic and imbued it with fire.
Then I predicted the trajectory of the minotaur's attacks.
Combat experience belonging to someone I had acquired in the Valley of the Dead.
Among it was that person's swordsmanship.
I brought the blazing blade down in a great overhead arc.
It shattered every weapon in its path to dust, then cleaved diagonally through the minotaur's torso.
"Ga—gahh..."
The bisected ox-headed creature collapsed to the ground.
I drove my sword into its back, forcibly draining its contained mana and miasma.
Now I had stripped it of any means of resistance.
There was no longer any worry it would attempt something strange.
I looked down at the critically wounded ox-headed creature.
The flame in its eye sockets flickered weakly.
"——Kill me. I am defeated."
The ox-headed creature murmured in a small voice.
The fierce aura from moments ago was gone.
Having lost its strength, it seemed to have regained some composure.
Noticing this change, I shrugged.
"Kill you? What do you think I created you for?"
"…What… do you mean?"
The ox-headed creature asked suspiciously.
Its eye sockets' flame blinked rapidly.
I stated flatly,
"I want you to become my subordinate. I could force you to obey without question, but I wish to respect your free will as much as possible. Won't you lend me your strength?"
"…………"
The ox-headed creature stared fixedly at the hand I extended.
It was difficult to tell without an expression, but it appeared to be stunned.
Digesting my words, trying to grasp their meaning.
If it were to resist, I would have to employ harsh measures, but it was better to secure cooperation willingly.
A strong-willed undead was a valuable asset.
Its combat capabilities were impeccable.
Considering the future, it was precisely the kind of ally I sought to enlist.
A long silence fell over the chamber.
I added no further words, simply waiting for an answer.
"…………"
Eventually, the minotaur stirred.
The undead, its face pressed to the ground, awkwardly reached out and clasped my hand.