Kai's quiet muttering was not as quiet as he thought. A few of the prisoners nearby heard him.
Those who were familiar with the powers of the New World understood exactly what he meant by 'Haki'. The rest were just left confused, whispering the strange word to themselves.
In the endless prison of Impel Down, time had no meaning. There was no day or night, no changing of the seasons. On Level 5, the Freezing Hell, there was only the biting cold and the endless, blinding white of the snow.
Another month slipped by in the blink of an eye.
Kai had now been imprisoned in the Freezing Hell for a total of two months.
With his 100-times training speed, those two months were the equivalent of more than sixteen years of non-stop training for a normal person.
For perspective, Monkey D. Luffy was only seventeen when he set sail. His journey from the East Blue to the Sabaody Archipelago took only a few months. Even after his two years of intense training, Luffy was still only nineteen years old, and his growth in that time was considered immense.
Kai had just experienced the equivalent of more than sixteen years of growth in just sixty days.
After such a long and intense period of training, he had hit a plateau. Whether it was his martial arts or his swordsmanship, he had reached a bottleneck. To break through to the next level, he needed more than just simple accumulation.
He needed experience. He needed a real fight.
Inside the cell, Kai stood before the massive iron door, his simple ice blade held ready. He took a deep, centering breath.
"Haaaaah!"
SHING!
A flash of cold light sliced through the gloom. In Kai's hands, the ordinary blade of frozen water moved with the grace and power of a legendary named sword. It bit deep into the prison door, carving a clean line through the metal.
He followed the slash with a powerful kick.
BOOM!
The section of the door he had just cut exploded outwards, leaving a gaping, two-meter-wide hole.
For weeks, Kai had used the door as his training target, relentlessly attacking it and leaving deep gashes all over its surface. This final attack was different. It was infused with the essence of what master swordsmen called the 'breath of steel-cutting'. It was a technique that allowed one to slice through iron as if it were paper.
The blow cleaved the metal, yet the fragile ice blade in his hand didn't even chip. This was proof that his swordsmanship had reached an entirely new level.
This single, explosive act was witnessed by everyone in the nearby cells. Pupils contracted in shock. A stunned silence fell over the prison block.
'Th-That's impossible!'
'Ain't no way!'
'He broke the door… with a blade made of ice?!'
The sheer reality of what Kai had just done was something most of them refused to believe. They all remembered when he first arrived. It was obvious to everyone that he was a complete amateur with a sword.
And now, in just two short months, he had gone from nothing to being able to cut through the hardened steel of a Level 5 prison door with an ice blade.
That was the skill of a true Master Swordsman. It was a level of mastery that most swordsmen failed to reach in their entire lifetime. How could anyone possibly achieve it in two months?
Kai's progress was no longer just impressive. It was terrifying.
At this moment, he was, without a doubt, stronger than ninety-nine percent of the prisoners in the Freezing Hell.
"Haaaah."
Kai ignored the stunned silence and whispered doubts of the other prisoners. He stepped through the hole he had created, planting his bare feet on the fresh snow outside. He let out a long, slow breath, the steam pluming from his lips.
Even though he was still trapped within the great prison of Impel Down, stepping out of that small, cramped cell felt like a taste of freedom.
After two months of constant training in the extreme cold, equivalent to sixteen years of adaptation, his body no longer felt the chill. He was used to it. Or rather, his physical strength and fortitude had grown to the point where the sub-zero temperatures simply didn't affect him anymore.
His dramatic exit did not go unnoticed. The silence was finally broken by a series of calls from the other cells.
"Yo, little bro! Just stepping out for some fresh air? Or are you planning on leaving for good?"
"Hey, if you're planning a breakout, you can't just forget about us!"
"Kai, my friend! Surely you remember all the helpful pointers I gave you…"
"We are willing to lend our strength to your cause!"
"If you're thinking of starting a pirate crew, I would be honored to serve under your command, Captain Kai!"
The calls were a mix of tones. Some were clearly joking, trying to lighten the grim atmosphere. But others were using a joking tone to mask a serious, desperate question. They were testing the waters. If Kai was truly making a break for it, they would follow him without hesitation.
After all, they were all facing sentences of decades, even centuries. Death by execution was always a possibility. Rather than sit here and wait for the end, they would gladly risk everything to follow this monster on a mad dash for freedom.
In truth, for the past ten days or so, no one had offered Kai any advice. The simple reason was that there was hardly anyone left who was qualified to teach him anything. In both martial arts and swordsmanship, Kai had surpassed almost all of them.
His physical power was immense, and he was unknowingly brushing up against the very edge of understanding Armament Haki. He lacked the proper method to unlock it, but if someone were to teach him, his current stats and training speed would allow him to master it in no time.
As for his swordsmanship, the proof was right there in the ruined door. Cutting through that metal with an undamaged ice blade was the feat of a Master Swordsman, and not an ordinary one at that. The doors in Level 5 were made of a special steel alloy, ten times harder than normal metal.
Even Kai himself probably didn't fully understand how strong his swordsmanship had become. He only knew the concept of cutting steel from his memories of Zoro and his master, Koshiro. He had reached this level through pure, relentless trial and error, guided by those faint memories and accelerated by his 100-times training speed.
For him, two months of摸索 was the same as sixteen years of dedicated practice for someone else. With that much effort, achieving this result wasn't so surprising. Zoro may have been a genius, but it still took him over two years of training under the world's greatest swordsman, Mihawk. Kai didn't have a legendary teacher, but his sixteen years of equivalent experience made him no less formidable.
"I'm going into the forest for a bit," Kai announced to the watching prisoners. "I need to get some real combat experience."
He didn't wait for a reply. He simply turned and walked away from the cells, his figure disappearing into the snow-covered trees.
He wasn't lying. He craved a real fight to test his new limits and accumulate combat experience, which would also grow at a hundred times the normal rate. Slaying the wolves in the forest would be trivially easy for him now, but the experience gained would still be valuable.
However, the prisoners left behind in their cells saw it differently. To them, his words were just an excuse, a cover story.
They believed he had just given them an invitation. An invitation for anyone serious about escaping to break out of their own cells and follow him into the forest, where they could discuss the details of the prison break in private.