"Hold the line at all costs! Do not let them break through, no matter what!"
A lone soldier—the captain charged with defending this position—bellowed his orders.
Then, a spear drove clean through his face.
It was the work of a Skeleton that had lunged forward in a reckless, suicidal charge. Though the creature was immediately cut down by the surrounding soldiers, the damage to our side was negligible. The achievement of crushing their chain of command was far more significant.
Besides, whenever I channeled Miasma into them, the shattered Skeletons would simply stand once more, throwing themselves at the living in another desperate assault.
This was a city in the northern reaches of the kingdom. I was currently leading an invasion force of one hundred and twenty subordinates. After shattering the main gate with my magic, I was now advancing toward the Lord's Manor, adding every soldier who fell before me to the ranks of the Undead.
"Damn it, they just keep coming...!"
"If you have time to whine, shut up and fi—"
"Tch, they're even using bows now!"
The soldiers were being forced into a brutal, losing battle. They had no answer for the arrows raining down from the Undead archers. Even when they managed to strike back and destroy a few, it did little to thin our ranks. To make matters worse, the Undead vanguard continued to throw themselves at the line, utterly indifferent to the damage they sustained.
Among the ranks were several Ogres braced behind massive shields. These were monsters from Luciana’s group, and I had included them in this expedition on a trial basis.
The Ogres advanced, paying no mind to the soldiers’ desperate strikes. They swung their heavy clubs with monstrous strength, shattering the human formations in a single blow. Their thunderous roars sent waves of panic through the remaining defenders.
(Hmm, not bad at all.)
The Ogres were integrating well with the Undead host. There were no issues with them fighting side-by-side; in fact, they complemented each other perfectly. The Ogres would smash through the lines, and the Undead would swarm into the resulting gaps, widening the breach with zero regard for their own preservation. It was a flawless wave attack.
The Lord's Manor was now just ahead.
"O inferior humans! Prostrate yourselves before the Undead King...!"
Grom, commanding the host, raised his staff high. The gem embedded in its head pulsed with light, unleashing a Black Fireball. The sphere of darkness traced a high arc over the soldiers’ heads and slammed into the Lord's Manor.
Jet-black flames erupted, and the manor began to burn with unnatural ferocity. The soldiers were momentarily distracted by the sight, and in that heartbeat, the Undead and Ogres fell upon them with relentless cruelty.
Watching the scene unfold, I spoke to Grom.
"The goal this time is not total annihilation. Do not overdo it."
At my correction, Grom hunched his back and scurried to my side. He leaned in to whisper with exaggerated gravity.
"No, Demon King-sama. This is a necessary measure. If we are to force submission, the intimidation must feel excessive—that is the perfect amount."
Grom seemed strangely confident in his methods. I had warned him out of concern that he was becoming intoxicated by the slaughter, but it seemed he hadn't lost sight of the objective. Perhaps he was making his own calculated adjustments.
Returning to his position, Grom unleashed another Black Fireball.
"Fuhahahahaha! Behold my Abyssal Power!"
"............"
Seeing him so gleeful gave me a faint headache. I found myself worrying once more if he had truly kept his eyes on the goal. It seemed Grom had taken a far greater liking to the role of the villain than I had anticipated. Being feared by the masses was part of the plan, but his power was immense. If he failed to restrain himself, he might accidentally wipe the city off the map.
That would be a problem. I would have to keep a close eye on him to ensure his actions didn't escalate too far.
Before long, we scattered the remaining soldiers and reached the Lord's Manor. We suppressed the interior in minutes and located the Lord, the ruler of this city.
"D-Don't come near me! You filthy Undead!"
The Lord shrieked, scrambling backward across the floor. His guards had already been butchered and transformed into Ghouls; there was no one left to protect him.
"...You. Do not think your death will be a mercy. After I have seen the end of your agony, I shall make you live bait for the beasts."
Grom’s voice was low and lethal. It seemed he could not forgive the man’s insults. Personally, I thought "filthy Undead" was a fairly accurate description of my current state.
"I will take it from here. Step back."
"At once!"
At my command, Grom stepped back instantly and knelt. He was as obedient as ever.
"The Undead who destroyed the Royal Capital..." the Lord stammered. He was drenched in sweat and deathly pale. I thought he might faint if I left him be any longer.
I looked down at the pathetic man. "You are the Lord, I presume."
"And if I am... what of it?"
"Then I shall be the one to end you."
I seized the Lord by his throat and hoisted him up, slamming him against the wall.
"A-gh, guh...!?"
His eyes rolled back in his head, his limbs thrashing wildly. White smoke began to curl from his skin as it discolored and started to melt. His flesh sloughed off in wet, liquefied tatters. The man rotted at an impossible speed until his bones finally clattered to the floor, leaving nothing but a dark, stained liquid at my feet.
"...Now then."
I turned my head toward the corner of the room. A group of humans huddled there, trembling uncontrollably. It was the Lord’s wife and children.
"If you do not wish to share his fate, submit to me. Do so, and I will spare your lives."
"Hi-Hieee...!"
The family collapsed in terror at my ultimatum. I doubted they had fully processed the words, but pressing them further would likely be counterproductive. They had been given a sufficient dose of fear; I doubted they would attempt anything foolish.
The Lord of this city had tried to seize territories left in a power vacuum by our invasion. He had prioritized his own greed over the survival of his people, caring nothing for the threat of the Demon King so long as his own pockets were lined. Such a man had no place in the world I intended to build. That was why I had made an example of him.
"We’re leaving."
I turned on my heel and gave the signal. The Undead host withdrew from the manor in silence. We walked back through the quiet, blood-slicked streets.
"My, my, as expected of the Demon King-sama! A truly masterful performance!" Grom praised me as he busied himself wiping my hands with a handkerchief.
I merely shook my head. "Enough flattery. What is the status elsewhere?"
"Yes. Lords across the regions are declaring their submission to the Demon King-sama one after another. Our public purges seem to be having the desired effect. If we keep this up, conquering the entire continent will be more than just a dream!"
"I see."
I was satisfied with the report. About thirty days had passed since Luciana and the remnants of the Demon King's Army had arrived. I had been systematically dismantling the kingdom's defenses using Teleportation Magic, establishing the threat of the Demon King while simultaneously creating the conditions for humanity to finally cooperate.
I moved to eliminate any self-serving humans who sought to take advantage of the chaos, like the Lord we had just finished with. I had no desire for a world where people spent their energy dragging each other down. Those who lacked a sense of cooperation were worse than useless; they were a cancer.
Thanks to these efforts, the provincial Lords were choosing submission. It was a pragmatic choice. They knew that to resist was to invite the Undead into their homes. I did not intend to interfere with their daily lives; they could continue as they always had. Their oaths of submission were likely lies born of convenience, but I didn't care. It was only natural for them to look for a chance to rebel.
In fact, it was ideal if they were secretly coordinating with one another. I would allow their schemes to destroy me to proceed. Humans needed a common goal—the subjugation of the Demon King—to force them into cooperation.
Currently, I had designated the territories that had submitted, centered around the fallen Royal Capital, as the Demon King's Domain. On a map, our influence appeared vast. While my actual control was limited mostly to the capital itself, that was a minor detail. The fact that we had "conquered" nearly the entire kingdom on the surface was what mattered.
Having achieved my goals in this city, I activated my Teleportation Magic and returned to the Royal Capital with my subordinates.
As we stepped through the ruins of the main gate, Luciana was there waiting. She jogged over with a playful bounce in her step.
"Oh, Demon King-sama! Welcome back. You’re home quite early."
"The operation went more smoothly than anticipated. Your subordinates were a great help; they performed excellently."
The Ogres had proven their worth. While the Undead could have eventually broken the defenses, the speed of the invasion was in a different league with the Ogres involved.
Luciana puffed out her chest with pride. "Right?! I trained them personally, you know! I’m honored they could be of use."
She narrowed her eyes, closing the distance with a sultry expression. She reached out to stroke my arm, whispering softly. "Say, Demon King-sama... since you’re back, how about some tea? Just the two of us, of course—"
"Demon King-sama! You must not listen to this woman! She is undoubtedly plotting something lewd!"
Grom’s inevitable interference cut her off. It was a familiar routine by now, and since it was harmless, I didn't bother stopping them.
Luciana, pulled away by Grom, put a finger to her lip thoughtfully. "Well... I mean, it is a little lewd, in a way."
"Did you hear that, Demon King-sama?! A confession at last! You shameless Succubus, I shall personally deliver your judgment...!"
"Quiet, both of you. Save the bickering for later."
When I gave my light warning, both of them turned toward me and retorted in perfect unison.
"We aren't bickering!"
"We aren't bickering!"
Seeing them so perfectly synchronized, I couldn't help but think they actually got along quite well.
Leaving the two of them to their sparks, I began the walk back to the castle. Grom and Luciana followed immediately, their argument forgotten as quickly as it had started. As we walked together, I looked around at the changes in the Royal Capital.
The city had been transformed. Goblins were running through the streets carrying construction materials. Orcs were busy repairing damaged buildings with heavy tools. Across the street, Kobolds were diligently tilling a new field in a vacant lot.
Succubi soared through the air, salvaging supplies from abandoned parts of the city. A Rubble Giant had taken a humanoid shape and was systematically clearing away debris. It was likely a Golem acting as someone’s familiar.
These were all members of the Demon King's Army who had followed Luciana. Since I had granted them permission to live in the Castle Town, they had begun developing the city of their own accord. They were laboring every day to improve their new home.
Among them, I even saw a few humans—former slaves who had been with the monster groups. They were being put to work for their specialized crafts or manual dexterity. Some could even use magic, and though they still looked a bit awkward in their surroundings, they were adapting with surprising resilience.
I found myself impressed by the sight. "Urban development seems to be progressing well."
"We’ve spent the last ten years learning how to build and survive," Luciana said. "We had to, or we wouldn't be here. The Miasma is a bit thick, but as long as we keep that managed, this is a beautiful place to live."
"Naturally. It was once the Royal Capital, after all."
I had concentrated the Miasma pervading the city toward the castle itself to prevent it from harming the monsters and humans living below. High concentrations of Miasma were toxic to the living, but with my adjustments, they could now live here without issue.
As for the massive host of Undead, they were stationed in the castle’s depths or in the city's warehouses. Their numbers had ballooned during our regional expeditions, and those that couldn't be housed inside were left to patrol the outskirts of the capital. In terms of raw numbers, they remained my greatest military asset. I intended to treat them with care.
Back at the castle, I stood on the balcony and looked out over the city. It was an incredible sight. A region once choked by Miasma and death was functioning as a center for life once again. Moreover, humans and monsters were coexisting.
It was a vision I never would have dreamed of when I was a human Sage. It was truly magnificent.
I desired true world peace, and I welcomed peace in this form as well. Even if it was only within the walls of a single city, seeing residents of all races living together brought me a sense of joy. Ideally, I would see this realized on a global scale, but I knew how difficult that would be. Flaws would eventually appear. This harmony only worked because it was a controlled, small-scale environment.
(To create peace on a global scale, the most effective solution is still the presence of a Great Evil.)
Of course, now that I had taken these people in, I fully intended to protect them from any external threats. They were the citizens of my nation. In exchange, they would build the foundation of the Demon King's Domain. It was a perfect arrangement of mutual interest.
Just then, a sharp war cry drifted up to the balcony. I looked toward the source—a large clearing that had once been the training grounds for the Knight Order. A group of monsters was conducting mock battles, training voluntarily for the wars to come. It was a promising sign.
(I must live up to their dedication...)
Through our successful campaign, I had seized control of over seventy percent of the kingdom. Total dominion was only a matter of time. From here, I would begin to expand the theater of war. The invasion of foreign lands was next.
(How will the other nations react as the situation escalates? That is the crucial question.)
Currently, the world was silent. They were likely assuming the Undead threat was a localized problem within the kingdom, choosing to wait and see how things developed. The ruling classes of the neighboring countries were far more optimistic about this new Demon King than I had expected.
Therefore, I decided to move more aggressively.
I had no intention of letting the emergence of a new Demon King remain a disaster confined to a single kingdom. I would drag the entire world into this and stir the pot until it boiled over. I would not allow anyone to treat this as someone else's problem.
I would show them the true power of the Undead King.