World Core and The Isolated Core

Caspian approached the sword.

He hesitated for a moment before reaching out, his fingers brushing the hilt.

AGHHH!

A sharp pain shot through his body, forcing him to his knees.

He clutched his chest, gasping for air as the pain suddenly vanished as quickly as it came.

{Hello, child,} a voice came.

Caspian's head snapped up.

"Who's there?" he demanded, looking around.

The room was empty.

{Hey, child. Look at me,} the voice said again, {I'm in your hand.}

Caspian blinked and stared down at the sword, his brows furrowing.

"Wait… you can talk?"

{Of course, I can,} the voice replied.

Caspian's mind raced. A talking sword?

'Am I losing my mind?,'

{I can also read your thoughts,} the sword interrupted.

"What? You can read my thoughts?" Caspian exclaimed.

The sword snickered.

{Relax, I'm not interested in whatever nonsense goes on in your head. Now, let's focus on the matter at hand, shall we?}

Caspian cleared his throat.

"Fine. Put that aside for now. I've completed your trials, so grant me power."

{I am your power, child,} the sword replied.

{I am your prize.}

Caspian stared at the blade, disbelief etched across his face.

"Wait… what?"

{I am the power you sought} the sword explained.

"So, show me your power!" Caspian demanded. "What can you do?"

The sword chuckled softly, a sound that made Caspian's irritation flare.

{I can't particularly do anything right now. That's because you are… how do I put this delicately… utterly useless.}

"Excuse me?" Caspian's grip tightened on the hilt as his temper flared.

"Are you seriously blaming me? What kind of excuse is that?"

{It's not an excuse; it's the truth,} the sword replied nonchalantly.

{My strength comes from the one who wields me.}

Caspian groaned, running a hand through his hair.

"So, let me get this straight. I just survived your ridiculous trials, nearly died, and now I'm stuck with a sword that insults me?" Caspian asked.

The sword hummed in mock thought.

{Yes, that about sums it up. But don't worry, child. As you grow stronger, so will I. Consider it a partnership.}

"Oh my god, what the actual fuck! You're useless! Completely useless!," Caspian shouted. His frustration overflowing.

"I went through all of this for you! And you don't even have any power? Do you realize I needed instant power, something to save my life—my miserable, pitiful life?" Caspian ranted.

He stopped pacing, gripping the hilt of the sword tightly, his breaths shallow.

"What am I going to do now? Oh god… am I going to die? Is this how it ends?"

The sword remained silent, its earlier sass absent as Caspian spiraled further.

"If I go back to the Arcwright estate, they'll kill me with their beatings. They've already broken me once—what's stopping them from finishing the job?" Caspian muttered, his voice cracking.

"And if I run away…" His thoughts raced.

"Then what? More problems. So many more problems." He began listing them, his tone growing more desperate.

"First, the Arcwright family will come after me. I'm their property, their blood. They won't let me go that easily."

"Second, if by any chance I get into trouble out there—bandits, beasts, bounty hunters—how the hell am I supposed to survive? I've got nothing!"

"Third…" Caspian paused, swallowing hard.

"Slavery. If anyone catches me wandering around alone, they'll sell me. I'll be worth nothing more than a few coins."

He clenched his teeth, his eyes burning with unshed tears as he stared at the sword in his hand.

"I thought you were supposed to be the solution. The reward for all my suffering. Instead, I get… you. A useless hunk of metal with an attitude problem!"

Still, the sword said nothing, its earlier confidence replaced with silence.

Caspian's grip loosened slightly as the weight of his situation pressed down on him.

"So many problems. So much danger. And I have nothing. Nothing except this… this useless shit!"

THUD

He collapsed onto the floor, the sword lying limply in his hand.

"Why? Why does everything I try end up like this?"

For a moment, the room was still. and the sword in his hand remained quiet, offering no answers.

The sword's voice broke the silence, regretful.

{I am sorry, child… for being useless,} the sword said.

"...."

The sword continued.

{But as I said earlier, how were you able to clear the first trial if you are this weak? With the mentality of a 9-year-old, you shouldn't have been able to pass it.}

Caspian frowned.

"What are you trying to say?," he asked.

The sword's tone shifted.

{No… wait a minute. How is this possible? No, it can't be…}

"What? What's wrong now?" Caspian asked, his irritation bubbling up again.

The sword ignored his question.

{Your core… it isn't connected to the world's core. No, this isn't possible. How is this possible?}

Caspian's brow furrowed.

"What are you talking about? What's a core?" Caspian asked.

He hadn't read anything like this in novel.

The sword hesitated, then spoke cautiously.

{Wait what?}

{Your mental age is around 16 years old, but your body seems to be around 9. That's not normal.}

Caspian's eyes widened.

'Oh… it must be because of my previous life,' he thought.

The sword's tone turned sharp.

{Previous life? Explain yourself.}

Caspian sighed.

"I lived another life before this one. I died and… I guess I ended up here. It's probably why my mental age is older than my physical one."

"But wait…" Caspian paused, scratching his head.

"I was 23 in my previous life. Does that mean my mental age was only 16 back then? Ugh, that's embarrassing."

"And if mine was 16, I wonder how much lower my friends' mental ages were… No wonder we were all such idiots." Caspian said as he chuckled bitterly for the first time in what felt like eternity.

{So, you possess memories of a previous life. This is the first case of its kind that I've ever encountered.}

"Yeah, yeah, I'm special. I get it," Caspian said, waving the sword's concern away.

{But it still doesn't explain why your core isn't connected to the world's core,} the sword continued.

Its tone was firm, almost as if it was more concerned about this revelation than the fact that Caspian had been reincarnated or transmigrated.

"Okay, now you're just throwing words at me," Caspian said.

"What is this 'world core' thing, and why does it matter?" Caspian asked.

{The core within you is your connection to this world's mana and life force. Everyone has one, and it's always connected to the world core—the source of all mana. Without that connection, you shouldn't even be alive, let alone capable of using mana.}

"But I can use mana," Caspian argued. "I've been using it to survive!"

{Exactly,} the sword said grimly.

{And that's why this is so strange. You shouldn't be able to. Your core is isolated, separate from the world. It's as if you're not truly a part of this world.}

"Not a part of this world, huh?....