One Piece: Buggy the Great King of the Sea

Rayleigh looked at the two of them with satisfaction in his eyes.

"You've both made incredible progress over this period," he said. "I've seen it with my own eyes. You're both fine young men. You're bound to carve out your place on the seas of the future."

Then, his expression turned more serious.

"I came here today to step up your training. At this point, your current regimen isn't helping much anymore. It's time to raise the intensity. Be mentally prepared—things are only going to get tougher from here."

Without another word, Rayleigh immediately laid out the next phase of their training. This time, there were major upgrades across the board.

Stamina Training: Now with Weighted Loads

Each of them would now run 200 laps, just like before.

But now they'd do it with 1,000 jin (~500kg) of weight strapped to their backs.

Swordsmanship: Underwaterfall Combat

Rayleigh found a massive waterfall hundreds of meters tall.

Buggy and Shanks were to practice sword techniques directly beneath the crashing water, for a fixed number of hours daily.

The waterfall would interfere with their balance, focus, and strength, perfect for building sword control.

Combat Sparring

Rayleigh would now spar with each of them individually for one hour daily.

Even though he held back considerably, facing one of the world's top swordsmen accelerated their growth dramatically.

It gave them real combat experience, improved their instincts, and helped refine their sword techniques faster than training alone ever could.

Physical Combat (Rokushiki)

There wasn't much change in the base training, except that sparring sessions were now added.

As always, actual fighting was the fastest way to improve hand-to-hand combat skills.

In a world without deathmatches or warzones, Rayleigh himself had to step in as their sparring opponent.

At first, both Buggy and Shanks struggled intensely with the new regimen.

Running 200 laps with 1,000 jin on their backs was brutal. Though they could finish it, they were left utterly exhausted.

Buggy, especially, felt like he was right back at square one. After every run, he'd collapse to the ground, unable to move, barely breathing. If Rayleigh hadn't been nearby to assist him, the crushing stones on his back might've flattened him completely.

Training under the waterfall was a nightmare. Standing upright under the torrent was hard enough—swinging a sword was nearly impossible. They both fell countless times before they could even stay balanced. Once they began the actual drills, every swing felt like it was costing them their lives.

Sword and physical sparring sessions were outright torture. Every day ended with bruises, cuts, and black eyes. Of course, they never stood a chance against Rayleigh—it was total domination. But the benefits were undeniable.

Despite the agony, the results were amazing. Just when their growth had started to plateau, this new training regimen pushed them forward again:

Stamina, swordsmanship, and physical skills surged across the board.

While they didn't break through to new realms of power, their combat ability, speed, reaction time, and striking strength saw massive gains.

Another three months passed.

By now, they were running their 200 laps with 15,000 jin (7,500kg) on their backs—basically like carrying a small mountain.

They had completely adapted.

They could now run all 200 laps with ease. Their stamina and endurance had been forged to a terrifying degree. Compared to who they were three months ago, they could exhaust their past selves purely through attrition.

Under the waterfall, they could now wield their swords as naturally as they once did on dry land. Their swordsmanship had evolved drastically in both power and precision. Even without breaking through to the next sword realm, their lethality was on a completely different level.

In terms of physical combat, they had both achieved mastery of the Six Powers. Combined with intense daily sparring, their combat instincts had been honed to a razor's edge. They still lost to Rayleigh, but no longer in a single blow. They could hold their ground for a short time.

Then one morning, Rayleigh returned to the island unusually early.

Without saying a word, he dropped several strange objects in front of them.

He brought:

A gigantic sword as tall as a man and as wide as two—like a steel door. The sheer weight of it left a crater in the ground.

A set of clothing and shoes, sleek and futuristic in design. High-tech—and also heavy, as they made loud thuds and left impact marks on the ground when dropped.

Rayleigh had specially commissioned the massive blade. The size and width would increase the impact of the waterfall, and the weight would build striking strength. The sword weighed over 5,000 jin (~2,500kg).

As for the clothes, these were custom-made weighted suits designed by the Germa 66 (Vinsmoke family) in the North Blue.

Each suit began with 5,000 jin of full-body pressure.

The tech allowed adjustments up to 20,000 jin.

For anyone else, these suits would've been impossible to obtain. But Rayleigh's name alone was enough. A single message from him had Germa scrambling to fulfill the order immediately.

Training with the suits was hellish.

The full-body resistance pushed every inch of their bodies to the limit. Every movement was an ordeal.

When the giant sword was added to the waterfall training, things became almost comical.

While they could stand under the water now, swinging the blade was nearly impossible.

More than once, the force of the waterfall hitting the blade dragged them straight to the ground.

Their hand-to-hand training became even more punishing. With 5,000 jin of added weight, they were once again punched into the dirt daily.

Then came the next stage: Haki Training.

Rayleigh knew time was running out. Word on the street was that Roger was ready to carry out his final plan. They had only a little time left before the crew's disbandment would become permanent.

So whether they fully awakened Haki or not, they needed to understand the principles and begin walking the path.

For Observation Haki (Kenbunshoku), Rayleigh designed a method he believed to be the most effective:

Blindfolded Combat Training – letting them rely solely on their senses to dodge incoming strikes.

For Armament Haki (Busoshoku), he didn't have a step-by-step guide. Instead, he would use it against them during their sparring matches, allowing them to gradually feel it, understand it, and learn how to use it in response.

And so began another brutal phase of their training.

Though they were constantly battered and broken, they grew stronger day by day, feeling pain and joy in equal measure as they stepped forward toward their future on the seas.