Halen didn't respond immediately.
He looked at Arin for a moment, as if deciding how much to say.
"Before I explain," he said, "tell me what you know about the core."
Arin paused briefly.
"It gathers and processes energy," he said. "And it connects to the body through the neural system."
Halen nodded.
"That's the basic idea."
He leaned back slightly.
"But that's not what matters."
Arin didn't interrupt.
"When the core begins absorbing energy," Halen said, "it doesn't stay contained."
"It spreads."
Arin's gaze shifted slightly.
"It moves through the body," Halen continued, "reaching every part of it."
"It strengthens the body."
He paused.
"And at the same time, it damages it."
Arin frowned slightly.
"The body adapts," Halen said. "It heals and becomes stronger over time."
"But the damage doesn't stop."
The meaning settled.
So strength came with a cost.
"It's a trade," Halen said.
"Strength in exchange for damage."
The room stayed quiet for a moment.
"So after cultivation begins," Halen continued, "your lifespan starts to drop."
Arin's thoughts paused.
This wasn't what he expected.
In everything he had known before, strength meant longer life.
Here—
it reduced it.
"How much?" Arin asked.
Halen looked at him.
"About half."
Arin didn't respond immediately.
So if someone had a hundred years—
they would only have fifty.
So time was already limited.
"That's why age matters," Halen said.
Arin nodded slowly.
The meaning was clear now.
"When the core stabilizes," Halen continued, "it shows how well it can handle energy."
"The earlier it stabilizes, the faster it absorbs."
Arin followed.
"A faster core means faster cultivation," Halen said. "Less time needed to progress."
"And if it stabilizes late?" Arin asked.
"You can still cultivate," Halen said.
"But everything becomes slower."
He paused.
"Much slower."
Arin remained still.
"If someone stabilizes early," Halen continued, "they might take eight to fifteen years to reach the next stage."
"If they start late, that time increases several times over."
Arin understood.
Time multiplied.
"And you don't have unlimited time," Halen said.
Arin's thoughts aligned.
He was already thirteen.
"So even if I try," Arin said, "I might not make it."
"There is a chance," Halen said.
"But it's very small."
The answer was direct.
Arin didn't look away.
"What happens if someone stops?" he asked.
Halen's gaze remained steady.
"You don't really stop."
Arin's eyes narrowed slightly.
"The core keeps absorbing energy," Halen said. "It slows down, but it doesn't stop."
"It fills, spreads, weakens, and then absorbs again."
Arin exhaled slightly.
So even doing nothing—
was still losing time.
"So having a core without cultivating…" Arin said.
"is worse," Halen finished.
The meaning settled completely.
This wasn't a choice between cultivating or not.
It had already begun.
Arin stayed silent for a moment.
"Is there a solution?" he asked.
Halen didn't answer immediately.
"There is one," he said.
Arin looked at him.
"Artificial cores."
The word stayed.
"They're not natural," Halen continued. "They're designed to stabilize energy more efficiently."
Arin listened.
"There are four tiers," Halen said.
"I only have confirmed information on the first three."
Arin didn't interrupt.
"Tier one is obtainable," Halen said. "Still rare, but possible."
"Tier two is costly. Considered a small treasure."
"Tier three—"
He paused.
"It's extremely rare."
"And dangerous."
Arin's gaze remained steady.
"If someone has it, others will kill for it," Halen said.
The implication was clear.
"For tier one, criminals might take the risk."
"For tier two, many will watch and wait."
"For tier three—"
He didn't continue.
Arin understood.
Even family wouldn't be safe.
"And tier four?" Arin asked.
Halen looked at him.
"Wars."
That was enough.
The room fell quiet again.
Arin's thoughts settled slowly.
Serum.
Cultivation.
Artificial core.
Each path had a cost.
Each path had a limit.
There was no safe choice.
Only the one he was willing to take.