A crowd of wolves had gathered outside Kai's cell, drawn by the scent of blood. But after killing a few for his meal, he paid them no mind. Killing any more would be a waste of energy. Their corpses would just pile up and freeze into solid blocks of ice.
Besides, wolf meat wasn't exactly delicious, especially when eaten raw.
There was no chance of starting a fire in the Freezing Hell. The temperature was far too low for a flame to survive. Any Devil Fruit users were shackled in Seastone, their powers nullified, and a normal person couldn't just will a fire into existence.
Still, food was food. It was better than nothing. At the very least, it gave Kai the raw fuel he needed to continue his relentless training.
Another ten days passed like this.
Kai's progress, which had been explosive at first, began to slow. He was hitting a bottleneck. The frozen prisoner he was using as a weight was no longer enough of a challenge.
He turned his attention to the other prisoners.
"You all aren't doing anything," he said, his voice cutting through the quiet despair of the cell. "Just sitting here is the same as sitting anywhere else. Why not help me with my training?"
The frozen man was only three meters tall. But there was another prisoner in the cell, a true giant who stood nearly seven meters high. If he could get that man to be his new training weight, the results would be incredible.
One of the prisoners, a weathered man with a long, frozen beard, looked up.
"Hey, kid. How long is your sentence? Are you getting out of here soon?"
Everyone locked away in Level 5 was facing a sentence of at least a few decades, if not centuries. For them, life was already over. They knew that escaping Impel Down was a fantasy. You couldn't just break out. You'd have to fight your way out. And to do that, you'd need to be stronger than a Marine Admiral.
It wasn't just difficult. It was impossible.
So no one bothered to train like Kai did. What was the point? Why get stronger if you were just going to die here anyway?
The only logical explanation for Kai's insane effort was that his sentence was short. Maybe five or ten years. If that were the case, it made a strange kind of sense. He would still be in his prime when he got out, so getting stronger now was a good investment for his future.
"I don't know how long my sentence is," Kai replied, his gaze unwavering as he looked at the giant. "All I know is that I'm going to keep getting stronger, no matter what."
He addressed the massive figure directly. "So, what do you say? Do me a favor and help me train. It's not like you have anything better to do."
The giant was silent for a long moment, his slow mind processing the request. Finally, a low rumble came from his chest.
"…Alright."
Just as Kai had said, the prisoners here had nothing to do but wait for the end. They would either starve to death, freeze into an ice sculpture, or be dragged away for execution. Their fate was sealed.
Since that was the case, helping this strange, determined kid train was as good a way as any to pass the time.
…
After that, the dynamic in the cell began to change. Kai's training sessions started to draw a crowd, and with the crowd came commentary.
"Hey, kid, you're doing it all wrong! That's not how you build real strength. Let me show you how it's done!"
"Hahahaha! Is that what you call swordsmanship? You can't just swing a blade around randomly and expect to hit anything!"
"Are you trying to practice the Six Powers? You'll never learn them like that. Your control over your own body is a joke. You need to start from the absolute basics. Master your own power first!"
Kai's training had become the main source of entertainment in the cell. Some of the prisoners were just watching for fun, shouting out insults to break the monotony. Others were genuinely bored and decided to offer a bit of guidance as they watched him work up a sweat.
Kai didn't care about their reasons. He took every piece of advice, every criticism, every insult, and absorbed it all. Even if most of them were just mocking him, he didn't care.
'If it can make me stronger, I'll take it.'
Every man imprisoned in the Freezing Hell was a notorious pirate with a bounty of over 100 million Berries. The weakest among them was a monster by outside standards. Some were likely worth 200 or 300 million. The truly legendary figures were kept one level below, in Level 6.
Among these powerful criminals, there were bound to be masters of martial arts, sword fighting, and even the Marines' secret techniques, the Six Powers. In the first half of the Grand Line, users of the Six Powers were rare. But for the veteran pirates of the New World, it was hardly a secret. Some of the prisoners here were even former Marines who had turned to piracy.
From the memories of his past life, Kai knew about the Six Powers. He wanted to learn them, but he lacked the fundamental knowledge, the core secrets of the art. Without a teacher, achieving the perfect level of physical control required was nearly impossible.
So when the prisoners started pointing out his flaws, it was exactly what he had been hoping for.
He could feel their advice making a huge difference. Each pointer, even those shouted as a joke, contained a kernel of truth from a seasoned fighter.
His control over his strength and his body became more precise, more refined.
His martial arts training grew more systematic, more efficient, targeting every muscle and every bone in his body for maximum growth.
His swordsmanship also became more structured. Soon, the simple ice blade in his hands moved with surprising and deadly grace.
As the days turned into weeks, the effect of his 100-times training speed multiplier became terrifyingly obvious.
Kai could feel himself getting stronger not just every day, but every single moment. The martial arts and sword techniques he was learning progressed at a phenomenal rate. His skills were changing and evolving daily, becoming more perfect and practiced.
And he wasn't the only one who noticed.
"This guy…"
"How long has it even been?"
"His ability to learn is just monstrous!"
"What kind of Devil Fruit did he eat?"
"No, look. He's wearing Seastone cuffs, but he's not affected. He can't be a fruit user!"
"Then… his talent is just that terrifying?"
The 100-times multiplier meant that one day of training for Kai was equivalent to a hundred days for anyone else. A few days for him was like a year of hard work for them. While he could feel his power growing internally, the prisoners could see the results externally. He was visibly changing, getting stronger right before their eyes.
In a single day, his swordsmanship went from that of a complete amateur to a skilled beginner who could use a variety of techniques.
The speed of his progress was simply horrifying.
Within a week, his skill with the blade was clearly proficient. He had gone from a nobody to a respectable swordsman in the time it took for the guards to deliver a few frozen meals.
The men watching him were all great pirates, veterans of the sea. They had the experience to know just how unnatural his growth was. At first, many of them assumed Kai must have eaten some kind of Devil Fruit, one that granted him an incredible ability to learn or enhanced his physical potential. They thought he was simply unlocking power that was already there.
But that theory fell apart when they looked at his wrists.
Kai was wearing Seastone cuffs. He was even training with heavy weights while wearing them.
A normal Devil Fruit user would be rendered as weak as a kitten by Seastone. They would barely be able to walk, let alone lift a seven-meter giant.
Therefore, he couldn't be a Devil Fruit user. And that fact made his terrifying progress even more unbelievable.