Mud stuck to his black boots. His cloak, dark as soot, fluttered slightly in the heavy forest breeze. The tall, twisted trees creaked silently. There was an unusual calm. A thick tension, as if the air knew what was coming.
Kazuo walked with steady steps.
Without haste.
Without fear.
In front of him, the earth had opened up into an irregular crater. Amidst vapours of heat and smoke, a monstrous, imposing body awaited him, covered in bone plates and stone scales. It breathed with a cavernous, almost mineral sound, as if each exhalation came from the mountain itself.
[ Area Boss Detected – 'Thraghul, Guardian of the Rock Crypt' – Rank B]
Kazuo stopped.
He did not draw his weapon. He did not need to.
Because his weapons were not made of steel.
They were his will. His body. And that thing that burned inside him when he remembered.
The creature roared with a bone-rattling din. Then it lunged forward like a tank without wheels, dragging rocks in its wake.
Kazuo slid to the left with agility. He dodged the first two claws. The third grazed him, his shoulder cracking under the impact. He flew several metres and rolled across the ground, kicking up dust.
He got to his feet in a single movement.
He was already bleeding.
'So, a B, huh...?'
But something didn't add up. That strength, that defence... they were above average.
The creature charged again. This time, Kazuo charged a wave of energy into his leg and released it just as he jumped, gaining a second in the air to avoid the attack.
It wasn't enough.
The boss wasn't just strong. It was intelligent. It changed its rhythm. It looked for his blind spot. That forced him to retreat more than once.
Kazuo clicked his tongue.
He activated his soul vision.
His field of perception was briefly tinged with pale blue, distorting the edges of his surroundings as if he were looking through water. The monster appeared shrouded in a dull mist, but on its back...
A point of light.
Tiny. Like a living crack.
A heartbeat.
A core that didn't beat like the rest.
Kazuo smiled slightly. A broken grin.
'There you are.'
He ran towards the boss. But not head-on. He didn't try to dodge this time.
On his way, he picked up a broken rock with his foot, hit it with a burst of energy, and threw it at the beast's face. The projectile did no damage, but it generated a cloud of debris that blinded his vision for a few seconds.
That was all Kazuo needed.
He activated a kinetic explosion in his heels. His body propelled itself as if catapulted from the ground. He spun downward. He skidded through the mud with his left knee bent, his right leg extended like a spear.
He passed under the creature.
And when his fist aligned with its core, he covered it with a dense, white wave of spinning energy.
Impact.
The creature rose from the ground. As if gravity had forgotten to hold it down.
And before it touched the ground, Kazuo appeared on its back. Another blow. Another crack.
And then...
BOOM.
The sound was sharp, like a tree split by lightning. The monster fell like a collapsing mountain.
Earth. Silence.
The monster had fallen. Kazuo stood still among the debris, his body tense, his arm still outstretched from his last blow. Energy still crackled on his skin, slowly dissipating into the air as if the world itself was still afraid to come near.
It had been a brutal fight.
The boss's body lay metres away from him, buried in a trench with its spine completely twisted. He hadn't screamed in pain or victory. He had just stood there in silence, watching the dust fall in slow motion around him.
Kazuo turned his head slightly and slid his finger across his interface. The stats should have been updated. But...
They were still the same.
'Tsk...' He frowned.
All the boxes for power, agility, defence, intelligence... were greyed out or filled with question marks. It was as if the system itself didn't know what to do with him. This was the fifth time it had happened. And this time, he stared at the menu a little longer.
Just below his main stats...
a new line lit up.
[Unique Ability: Archaic Core]
Description: —
There was no description. No category. No restrictions. Just the name.
Kazuo frowned. He didn't remember activating it. He didn't even know it was there.
'...Core?'
He tapped the interface, but it offered no information. No clues.
Just that name, like a shadow buried under layers of code.
In the control room of Aether's Realm
'...What the hell is this?' asked a technician, frowning as he scanned one of the main screens. His fingers paused on a line of code, unable to move forward.
'A new boss defeated... by the same player as always,' replied another, without taking his eyes off the data being updated in real time. 'But his stats are still unreadable. Everything appears as "???".'
'And that ability? "Archaic Core"... does anyone recognise it?'
The silence that followed was uncomfortable. Even the constant hum of the system seemed to diminish.
A woman sitting in front of a secondary terminal began checking internal system lines, accessing layers of data reserved for development and alpha testing.
'No... this can't be,' she muttered, her hands trembling slightly on the keyboard. 'This ability... isn't in the active system. It doesn't exist on any list of authorised abilities.'
'What do you mean it doesn't exist?'
"I mean it literally. "Archaic Core" is a concept. An experimental design that was never finalised. It only exists in the project's phase zero documents. There's no functional code loaded on the public servers. It's as if... the system brought it into being on its own.
From the floor above, a man slowly turned in his seat. Tall, with carefully combed grey hair and metallic grey eyes that seemed to see beyond the screen.
Ishiguro Sōma, senior supervisor of the game's emotional system.
'What is the player's name?' he asked, his voice deep but calm.
'Kazuo,' replied the nearest technician. 'Full ID confirmed. Although people externally label him as "Shiranai".
Sōma descended the steps without taking his eyes off the holographic projection.
'There are no matches in this game," he said, almost to himself.
He approached the main console. His eyes scanned the activation log.
'This isn't a mistake. "Archaic Core" was an emotional core. A module based on the synchronisation of instincts, willpower, accumulated trauma, and the player's psychic evolution under extreme pressure. It was discarded because...' He paused. 'No human mind could synchronise it in the simulations. None. They all collapsed at early stages.'
'Then... how did he...?'
'I don't know. And that's what worries me,' he replied coldly.
'What if it's a glitch? A validation error?'
Sōma shook his head slowly.
'No. The system doesn't create unauthorised abilities. And if it did on its own... then we lost control of the core. And that's worse.'
One of the younger assistants swallowed hard.
'What do we do?'
Sōma rested his hands on the edge of the console. On the screen, the recording of Kazuo — calm, expressionless — continued to play on a loop. His movements were measured. His gaze empty. He slid through the menus without blinking, as if he knew in advance that he would find no answers.
'Compile all your information. I want the complete history of that account: real name, date of creation, source server, link terminal, previous activity, behaviour patterns... everything.'
He turned to the team, his voice dry and precise.
'If we don't find anything irregular, if its structure is legitimate and the system still can't measure it... then we have a bigger problem than we thought.'
One of the technicians raised his voice cautiously:
'What do we do if the system really can't track it or limit it?'
Sōma held his gaze on the screen for a second longer.
'Then find out who it is. I want a complete psychological and behavioural profile. We're not talking about a bug. We're talking about a variable that the system isn't designed to contain.'
He paused, briefly but tensely.
'And if Archaic Core is really active, I want to know why. That ability shouldn't be available to anyone. Not even in testing.'
The technicians exchanged uncomfortable glances.
'What if the system assigned it autonomously?'
Sōma didn't respond immediately.
'Then it will be the first time the system has decided on its own which player should be... off limits.'
REALM & CO. CAFÉ – SHIBUYA, TOKYO
Screens floated above the tables. They projected slow-motion replays of Shiranai's last fight. The background music had been muted. Even the waiters served coffee with extra care, attentive to what the customers were saying.
At a table by the window, two young people were sharing space for the first time.
'So you come here to watch the broadcasts too?' she asked with a slight smile as she held a cup of hot chocolate.
'Every day since the third week,' he replied, adjusting his glasses. 'But this guy... I don't know. Shiranai is different. It doesn't even seem like he's playing the same game as the others.'
She nodded. Her brown hair fell naturally over her shoulders, and her voice, though calm, carried a keen curiosity.
'I'm Hoshino Mei, by the way. Systems analyst. Well, on hiatus. My whole company is following this full-time.
'Kurosawa Ren. AI development student. This is the closest we've come to seeing a bug with a will of its own.
They both laughed, but their eyes remained fixed on the screen where Kazuo — or 'Shiranai' — stood before a colossal monster.
'Have you noticed how strange its movement pattern is?' said Mei, leaning forward slightly. 'It doesn't fight like the others. It doesn't look for typical weak points. It creates them. It's as if it has battle knowledge that the system doesn't teach.'
'It doesn't seem to be using the traditional tactical system.' Ren tapped the screen to zoom in on a scene. 'Look at that... that turn... it's not a reflex.'
It's using the kinetic energy from the previous impact to propel itself. Who fights like that?
'Someone who didn't learn from simulations,' Mei said quietly.
'Did you see that?' Mei asked, leaving her tablet on the edge of the table. 'It just activated that ability again. "Archaic Core". Still no description.'
Ren, with his laptop open and three forum tabs open side by side, didn't take his eyes off the screen. His voice sounded serious, restrained.
"And look at his HUD. It's not hidden, but everything is still question marks. Health, strength, defence... all blank.
'That's not normal. The system always shows something. Even if you're just starting out.' Mei bit her lip, then lowered her voice. 'What if that ability was inserted manually? Not by the system. By someone.'
'Someone inside?' Ren looked at her sideways.
'Or someone with access. Maybe from before this started.'
Ren's eyes flickered as he switched to a tactical view of the menu.
'There's another option,' he said, resting his elbow on the table. 'That it's not a skill to "use"... but to "respond". That Archaic Core isn't an offensive or defensive tool. But a catalyst.'
'A catalyst for what?'
'Of him. Of his will. Of his emotions.' Ren narrowed his eyes. 'Haven't you noticed? The more cornered he is... the more unpredictable he becomes. As if the system can't calculate what he's going to do.'
Mei fell silent.
Then she murmured,
'Maybe that's why the data is blank. It's not that it doesn't exist. It's that it can't be measured.'
At the next table, a college girl with green-dyed hair let out a dramatic sigh:
'I'm in love! Did you see how he took out the boss with that spinning punch?! My ideal type is a glitch in a black hoodie!'
'What if he's not even a normal player? What if he's an undercover GM?' asked her friend in an exaggerated conspiratorial tone.
'If he were, don't you think he'd have legendary equipment, not worn-out trousers and bandages?' interjected a boy in the background.
At the bar, the bartender, in his thirties, muttered under his breath:
'He doesn't fight like a player. Or like a character. He fights like someone who's jaded. Like he's lost too many times.'
An older woman in a business suit sipped her coffee as she watched intently:
'We call him Kazuo, but that boy... he's not fighting for glory. Or revenge. It's like he only knows how to move forward. Even if there's no one waiting for him on the other side.'
'What if that ability was given to him on purpose?' Mei asked suddenly. 'What if someone within the system thought, "Only someone like him can carry this"?'
Ren frowned.
'Why would you want someone like that to have an indecipherable ability?'
'Because you knew you'd need it,' Mei said without hesitation. 'In this kind of game. In this hell.'
Ren was silent. And for the first time in weeks, he didn't know how to respond.
They both looked back at the screen just as Kazuo appeared walking down a lonely path. The defeated monster was already far away. There was no celebration. There was no recovery. Just his figure walking away.
Mei exhaled slowly.
'Sometimes, you don't need to know the ending. Just keep watching to see how far someone like him can go.'
'Or how far they'll let him go,' added Ren.
And then, almost in a whisper, Mei said,
'What if even they can't stop him?'
Ren blinked.
And for the first time, that idea—absurd, silent, dangerous—hung over the table.