In a cold, dark room, a young man in his twenties sat in a chair, his gaze fixed on the space before him.

  At first glance, he appeared no different from an ordinary human. However, a single look at his head immediately revealed the truth: he was anything but ordinary.

  A pair of horns adorned his head, a distinct indication of his demonic nature.

  What distinguished him from other demons was his reincarnation and the possession of a system that assisted him.

  That alone should have made him an immensely powerful being, a demon that instilled fear in all creatures. Yet, he was far from that. He wasn't one of the high-ranking demons that terrorized the world, no, he was much lower, a mere Lesser Demon, the lowest of the low, the scum of demonkind.

  When he first opened his eyes, he was greeted by the sight of a dark cave. Moments later, a torrent of unfamiliar memories flooded his mind, revealing just how pitiful the previous owner of his body had been.

  He was a Dungeon Lord.

  But what exactly are dungeons?

  Dungeons were realms where monsters were spawned from the demonic energy emitted by their Dungeon Lords. These locations existed separately from the mortal world, connected only by portals.

  Scattered throughout the world of Perans, dungeons play a crucial role in maintaining the balance of power.

  What was Perans, and where was it located?

  It was the name bestowed upon this planet by its inhabitants. Unlike Earth, Perans was a world where magic coexisted with advanced technology. The presence of magic had significantly accelerated technological development at an astonishing rate, resulting in a civilization far beyond anything Earth had ever witnessed.

  Yet, this technology came with a limitation: it could not function inside dungeons. The dense demonic mana interfered with all forms of advanced machinery, rendering them ineffective.

  Despite this, Perans flourished, expanding its reach to colonize nearby habitable planets. The civilization now controls a total of five worlds.

  But even with their vast interplanetary empire, their primary focus remained on Perans itself. Why was that?

  Dungeons existed solely in Perans, they were found nowhere else.

  Dungeons contained rare resources that could not be found in nature, making them invaluable.

  But how had Perans achieved such advancements in both science and magic? To understand this, one must first examine the races that inhabit this world.

  The two dominant races were humans and demons.

  Demons had once invaded Perans, bringing magic with them. In response, humans devoted themselves to scientific progress. The fusion of these two forces, magic and technology, led to breakthroughs once thought impossible.

  One significant breakthrough ensured an abundance of resources, alleviating concerns about scarcity. Famines became a relic of the past.

  At first, these advancements appeared insignificant, however, over time, they exerted immense pressure on the demons. Unlike humans, demons reproduce differently, resulting in a growing imbalance.

  As the human population grew, an increasing number of individuals embraced the role of adventurers, exploring dungeons in search of wealth and power. Ultimately, dungeons came under human control and were exploited for their resources.

  As more dungeons were conquered, competition intensified.

  With fewer dungeons available, opportunities for wealth dwindled, sparking a frenzy among humans. Greed took over. The weaker dungeons were quickly eradicated, leaving only the strongest. However, even those did not last long, they, too, fell before the relentless onslaught.

  If all the dungeons were destroyed, how was he here?

  Even though the greatest dungeons had been eradicated, new ones still occasionally emerged, though they had become a rarity.

  Some attempted to monopolize them, but none succeeded. Ultimately, greed prevailed. No one was willing to allow another to control such immense wealth.

  How did he know all of this?

  All demons were born in another dimension, and with their birth came inherited knowledge and a mission to conquer this world.

  This unending war between humans and demons ensured that no dungeon was spared and no resource was hoarded for its true value. The conflict had persisted for so long that there were only two choices: kill or be killed.

  His situation was dire. The strongest dungeon, which had kept humanity at bay, had been destroyed not long after his birth.

  With their fall, the more powerful demons abandoned this world entirely.

  Did he fear death? No.

  Why?

  Because all demons who died would return to Hell and begin anew. Death was merely a reset.

  This is why demons fought to their last breath: climbing back up from the bottom is the hardest challenge of all.

  But he was different. He was a newborn soul, unburdened by a past or enemies.

  Now, his sole concern was survival.

  His dungeon was under constant siege by humans, with wave after wave of attacks.

  They provided him no opportunity to repair the traps left by his predecessor, and his monsters were being eliminated far too swiftly. With no other options available, he resolved to redesign the first floor of his dungeon, depleting all his mana and terror points in the process.

  What were terror points, and how did he obtain them?

  This was his advantage: his cheat.

  The Terror System

  It enabled him to generate terror points by instilling fear in others. Unfortunately, his subordinates were exempt from this privilege.

  Each individual contributed a varying number of terror points, resulting in an unstable income.

  There was no upper limit to the amount a single person could contribute, but the real question was: how long could they endure the fear?

  With this in mind, he redesigned the first floor. Instead of a maze, he created a misty forest.

  A forest where the mist disoriented anyone who entered. The longer they stayed inside, the more intense the disorientation became.

  After completing the transformation, he felt his energy drain away, however, that was where his system came into play.

  He could exchange terror points for mana.

  One terror point is equivalent to ten mana.

  How much mana did he currently have? One hundred.

  However, his system remained incomplete. To unlock its full capabilities, he needed 1,000 terror points.

  The system granted him an initial pool of 100 terror points to assist in establishing his dungeon.

  It was a generous beginning, one that not all demons experienced. Most newborn demons perished within their first day, overwhelmed by relentless human assaults.

  So, what creatures inhabited the first floor of his dungeon?

  For the first time, he reflected on the ancient legends of Earth.

  One creature that came to mind immediately was the Wendigo.

  Thankfully, the Wendigos in his dungeon required neither food nor sleep.

  They could hunt for 24 consecutive hours.

  And with them, his reign of terror would commence.

  Other than that, I created birds that scream. Their voices, when frightened, mimic human screams, and I trained them to scream whenever they detect humans. This way, no one can discern whether the scream is genuine or merely a part of the trap.

  The foggy atmosphere, combined with the persistent, anguished screams, is sufficient to unsettle anyone's nerves.

  At first, I contemplated setting up traps, but ultimately, I decided against that approach. Instead, I decorated the entire forest with decapitated human heads, their skulls embellished with antlers.

  The grotesque scene may repel weaker minds, but it fills me with a sense of ecstasy.

  In my previous life, I was confined to a dismal mental hospital. They labelled me as insane and condemned me to a life devoid of any contracts with other humans.

  The agony I endured there, knowing I was innocent while the world around me remained blind to my truth, was unbearable. They didn't even know who they had arrested. They mistakenly accused me of someone else's actions, claiming I killed 77 people. But where did they get that number? I killed closer to 300, and those 77 had nothing to do with it.

  What I pursued for pleasure, they labelled as a crime.

  The thought of witnessing people move through the streets without fear, blissfully unaware of the darkness in the world, drove me to madness. They apprehended me before I could continue my work. I couldn't take lives for pleasure, yet they could relish their existence, untouched, while I remained imprisoned because my "fun" cost innocent lives.

  I told them the truth they asked why I did it. I explained that it was my daily source of entertainment, my source of dopamine.

  And for that, they confined me.

  I banged my head against the walls, yearning for release, but they confined me, preventing me from harming anyone or myself.

  I spent 88 years of my life in that hellhole before passing away at the age of 133.

  The torment of being unable to inflict harm on anyone, to kill or injure, drove me to the brink of insanity.

  But then, as if the gods had heard my pleas and granted me justice, I was given a second chance.

  Now, I could finally kill without the fear of being caught. And even if I were, I could start over.

  If this isn't heaven, then what is?

  I can still picture the faces of my victims as the wendigos on my first floor tore them to shreds.

  When creating monsters for your dungeon, their strength is determined by the amount of weakness you imbue them with and the mana you expend. A monster's power is limited by the strength it can withstand, making weaknesses essential for crafting more formidable creatures.

  For my wendigos, I created weak deer antlers. Even the slightest touch can kill them instantly.

  Did I decorate my entire floor with antlers? Yes, while most of them are fake, one is real.

  How many antlers are there? Probably around a thousand.

  Am I worried that this information might be leaked to the outside world?

  If humans grow bolder and venture deeper into my dungeon, I would be delighted. It would be amusing to shatter their hopes as they attempt to wield the fake antlers as weapons.

  I can already envision their despair.

  Thousands upon thousands of screams will echo throughout the world as they plead for an end to their suffering. Yet, I will merely prolong their anguish, providing false hope only to witness them descend into despair time and time again. Rinse and repeat.

  Sometimes, I allow them to escape into the outside world, but when a dungeon break occurs, I track them down until they have exhausted their last shred of usefulness.

  What a perfect plan! They will gladly contribute to the creation of my paradise.

  Before all that, I need to construct a second floor. The humans are getting closer and closer to my room.

  I know how to fight, but I choose not to.

  Dirtying my hands with the blood of these lesser creatures? Never again. I have come to understand my mistake in my past life: I had no one else to blame.

  They blamed me for 77 deaths, but it wasn’t my fault. It doesn’t matter now, they can never pin it on me.

  I will ensure that my subordinates are held accountable for all the atrocities.

  With those happy thoughts in mind, I returned to the present, although my boredom was increasing. The sight of the wendigos tearing people apart, limb by limb, no longer excited me.

  At first, it entertained me, however, after watching the same thing repeatedly, it has lost its appeal.

  I cannot increase the number of Wendigos beyond 30, as each floor has a limit on the number of monsters. The dungeon itself must expand to accommodate more creatures.

  I already have a plan for the second floor, but to implement it, I need to advance to a mid-level Lesser Demon.

  Each demon tier is divided into three subcategories.

  From a Lesser Demon, I ascend to a Middle-level Lesser Demon and then to a High-level Lesser Demon.

  After that, the Common Demon appears.

  From what I understand, my appearance will change as I progress in levels.

  Even though I appeared the same as I did in my twenties, with horns protruding from my head, other demons regarded me as little more than an imp.

  But I don’t care what others think. All that matters is my happiness.

  I can only watch, disinterested, as humans wander into my dungeon, reacting almost identically to those who came before them. It is becoming tedious.

  ***

  My name is Dane, and this is my first dungeon conquest.

  I was incredibly excited to have been selected for this dungeon conquest, I couldn't sleep at all that night.

  As I entered the dungeon, I scanned the area for the usual monsters: goblins and kobolds, the types that typically appear on the first floor of most dungeons.

  However, what awaited us was something completely different.

  A fog-shrouded forest emanates an eerie atmosphere.

  Kid, don’t pay attention to all the nonsense about dungeons you read online. New dungeons spawn various creatures, but because they are connected to older dungeons, they can generate more powerful monsters. This place doesn’t seem particularly special.

  I glanced over my shoulder to see a middle-aged man with his hand resting on my shoulder, trying to ease my evident fear.

  “Also, kid, keep your guard up. The dungeons that aren't connected to the higher ones are trickier to conquer. You need to be prepared for anything,” he added, withdrawing his hand and giving me a stern look. I could only listen, fully aware that many adventurers were prohibited from discussing dungeon matters publicly.

  So, the new dungeons weren't dangerous after all? I wondered.

  That boosted my confidence. Conquering this dungeon would be a breeze, and the rewards for doing so would be extraordinary!

  I was no longer worried about how I would support myself for the rest of my life. However, when I looked at the middle-aged man again, I could see the burden of his experiences etched on his face. He must have been just as eager when he was my age, but reality had taught him a different lesson.

  “Everyone, gather here!” a commanding voice interrupted my thoughts. A man in military attire stepped forward to address the group.

  “Our mission is to gather information, not to conquer. Anyone who disobeys will be tried in a military court!” he commanded. The military had staked its claim to this new dungeon.

  The mood quickly soured. Gathering information was one thing, conquering it was another. One brought glory and fortune, while the other barely provided enough to survive.

  But who would dare to oppose the military, especially after the empire had united the entire world and colonized numerous planets?

  Most people appeared downcast, but I held on to a glimmer of hope.

  If I could defeat the dungeon lord on my own, I would be able to claim all the rewards for myself. Guilds would eagerly seek to recruit me, and I would never have to worry about the military again.

  I clenched my fist, fully aware that this was my only opportunity in life, and I had to seize it.

  “Now, everyone, form a team. If you do not, I will assign you one.” The military captain’s voice was authoritative. He understood that some would attempt to claim glory for themselves, but that worked to his advantage. They would eliminate the monsters, and he would reap the rewards.

  What no one realized was that their meeting had attracted the attention of the local creatures lurking in the fog, patiently waiting for the perfect moment to strike.

  ***

  My teammates include an uncle who shared information about dungeons, along with three others: two women around the age of 25 and another middle-aged man. The military assigned us to four separate groups, bringing the total number of participants to ten.

  Each group was assigned to explore a different section of the forest, while the military stayed at the entrance. We were instructed to notify them if we discovered the entrance to the dungeon lord’s chamber.

  Looking at my teammates, I could tell that everyone wanted the reward for themselves. However, I knew I had to be the one to earn it.

  They were all in their thirties or older, while I had just entered my twenties. I had significantly more time ahead of me, and this opportunity was mine to seize.

  “Ah!” A scream echoed from the forest, faintly resonating in the distance.

  Instantly, we all assumed a defensive stance and rushed toward the sound, eager to support the group that had been attacked. We hoped to defeat the monsters ourselves if we arrived in time.

  As we approached the source of the scream, we encountered a disturbing and grotesque decoration in the dungeon.

  I nearly vomited when I saw it: a head adorned with antlers.

  The face was frozen in horror, though it was difficult to discern the exact expression, as its eyes had been gouged out, leaving hollow, bloodstained sockets.

  What had it witnessed before its demise? What kind of monster could commit such an atrocity? Or was this the work of the dungeon itself? Struggling to steady myself from the shock, I glanced at the others, but their expressions reflected my own.

  So, is this not typical in other dungeons? They appeared visibly shaken, but they quickly regained their composure upon seeing more corpses. For many of them, this was their first encounter with such brutal violence.

  Whoever designed this dungeon was unhinged.

  It is understandable why so many people sought to destroy dungeons not only for the glory but also to avenge those who had perished before us.

  We could only move past the grotesque head and continue toward the source of the scream, but then another scream echoed from the direction we had just left.

  We began to grow suspicious. Were these screams part of the dungeon's trickery? We hadn't encountered any other adventurers, which led us to question whether we had been deceived.

  Realizing that we had been misled, we abandoned our pursuit of the source and returned to our original mission: gathering information about the dungeon.

  We noted that some creatures in this dungeon can mimic human screams, potentially serving as a warning for future adventurers, assuming I do not defeat the Dungeon Lord before that happens.

  For now, we had no choice but to ignore the strange sounds and remain focused on the task at hand.

  But we had no way of knowing that the screams we had heard were, in fact, genuine. They had come from a soldier who had secretly followed us and met his demise at the hands of the dungeon's monsters.

  ***

  Several hours passed, yet we found no leads only the scattered remains of other adventurers: broken equipment, torn clothes, and bloodstains.

  There was nothing more to discover, so we could only conclude that a battle had occurred between the monsters and the adventurers.

  We decided to follow the bloodstains, which appeared to lead us back to the entrance of the dungeon.

  This puzzled us, as we had been traveling primarily in a straight line how could we have returned to the entrance?

  What shocked us even more was the realization that the soldiers were no longer present.

  It appeared that a fight had broken out, and the soldiers had retreated into the forest, leaving footprints in their wake.

  We exchanged apprehensive glances before proceeding in that direction.

  As we ventured deeper, we encountered the bodies of fallen soldiers, gruesomely mutilated from their battle with the monsters.

  Their stomachs had been torn open, with intestines spilling out around them, and one or two soldiers were missing limbs. One soldier even had his face mutilated.

  We counted a total of five corpses, although the captain and four others remain unaccounted for.

  “Should we retreat?” I asked, uncertainty creeping into my voice. Conquering this dungeon now felt like an impossible task. The noise we made had surely alerted the monsters to our presence.

  “Yes, this dungeon is clearly beyond our capabilities,” said the middle-aged man, his gaze fixed on the fallen soldiers.

  We turned to leave, intending to retrace our steps, but the terrain around us had shifted.

  After walking for what felt like an eternity, everyone's hopeful expression shifted to despair. However, I kept reminding myself that we only needed to go a little further to reach the entrance.

  “We must leave this dungeon,” I muttered softly.

  “Did we get lost?” the woman asked, clearly aware that we were walking in circles.

  “We’re close to the entrance,” I replied, attempting to reassure the group, though even I didn’t believe my own words.

  We had walked for an extended period without reaching the entrance or encountering any other groups.

  Then, through the fog ahead of us, I saw a pair of crimson eyes flicker to life.

  “Enemy!” I shouted to the others as a monster emerged from the mist, poised to attack us.

  The moment I shouted, everyone assumed battle-ready stances.

  The monster let out a terrifying screech and charged at us without hesitation.

  “Eeaak!” Its soul-chilling scream echoed as it drew closer.

  I raised my shield to block the monster's assault, but the force behind its charge was far greater than I had anticipated. I was sent flying, and the impact left my arms numb and immobilized. I couldn't feel anything.

  The monster, undeterred by my fall, turned its attention toward my uncle. He raised his sword, preparing to strike, but he was in no better shape than I was.

  “Magic missile!” one of the women called out, and a bluish magic missile materialized from her staff, striking the monster squarely in the head.

  “Eat this! Hahaha!” She laughed as the missile struck, confident that the monster would be weakened by the blow. No creature on the first floor should be able to withstand such an attack to the head, and even if it did, it would be significantly weakened.

  For a brief moment, we believed we had gained an advantage as the monster staggered backward. However, that glimmer of hope was fleeting.

  The woman who had cast the magic missile barely had time to celebrate before a claw pierced her chest from behind.

  We were shocked, but the other woman standing beside her froze in horror, unable to react in time.

  In an instant, the monster tore the woman's head from her body and tossed it aside, its gaze locking onto us.

  Three of us against four of them.

  The odds were stacked against us, but we had to persevere.

  I managed to push myself up, determination flaring in my chest. However, more pairs of eyes emerged from the fog.

  “There are too many of them! We can’t escape! What should we do?!” That was the last thing I heard before a claw shot toward me, and darkness swallowed my vision.