One Piece: The user of the Nen-Nen Fruit, who overturned the sea.

"Boss?"

"What's done?" Tesoro, who was doing push-ups, turned his head curiously to look at Roy.

"Tesoro, try out my newly developed ability."

Without waiting for Tesoro to get up, he directly covered him with the gravity field.

"Bang!"

With a soft thud, Tesoro, who was completely unprepared, was instantly slammed to the ground by an invisible force, sending dust flying.

"How does Tezzo feel?"

At this moment, Tesoro felt as if a small mountain was pressing down on him, his bones were trembling, and he could hardly move a single finger.

"Boss... what is this...?"

Seeing Tesoro lying on the ground, his face flushed red, Roy felt a pang of embarrassment and quickly adjusted the gravity on Tesoro, controlling it to the limit that he could bear.

"How is Tezzolo now?"

Tesoro struggled to lift his head, sweat quickly covering his forehead, his teeth clenched and the veins on his arms bulging.

Under twice the gravity, movements that are usually effortless become incredibly difficult.

"It's...really...amazing! But...boss, what exactly is this?" Tesoro said through gritted teeth as he slowly stood up.

"Hehe, it's dark~"

"Gravity—I'll call it the Gravity Domain for now. Within my domain, I can freely adjust the surrounding gravity. Isn't that much better than your simple weight training!"

Roy looked excited. With the help of gravity, his companions' strength should be able to improve rapidly, and he wouldn't have to worry about them in future battles.

Stella and Savi, standing nearby, swallowed hard when they saw Tesoro's miserable state. Their eyes filled with awe as they looked at Roy, as if they already knew their own fate.

Roy smiled, and his domain instantly enveloped the remaining two, gradually adjusting the gravity around them.

It allows them to move, yet it makes things incredibly difficult.

In the days that followed, the training on the back mountain entered a hellish mode.

Roy was no longer satisfied with simple physical combat and the guidance of domineering aura.

He set up many challenges in the field: a 300-meter zone with three times the gravity centered on himself, a 500-meter zone with twice the gravity centered on him, and a 1,000-meter zone with one times the gravity centered on him.

Furthermore, it would occasionally change the direction of gravity while the group was cultivating, creating a chaotic gravitational turbulence to enhance their adaptability. It would also keep the gravity active while they ate and slept, allowing them to quickly adapt to the intensity of gravity on their bodies.

Tezzolo is a particular focus of attention.

Roy knew he had considerable potential, but compared to himself and Bullet, his foundation was still too weak. If he didn't work hard now, he would only be able to reach the level of one of Kaido's three calamities in the future.

So Roy focused his attention on Tesoro, since he was his first underling!

Under the relentless torment of gravity day after day, Tesoro's physical abilities increased at an astonishing rate. He gained more refined control over his own strength, and more importantly, his will became even more resilient through repeated struggles to the limit.

Stella and Little Savi were no exception; as they adapted to gravity, everyone's physical fitness and ability to adapt to abnormal environments improved rapidly.

It has been a year since Roy arrived on the island.

Roy has turned 12 and grown to 2 meters tall. His long golden hair is draped behind him. He is wearing a black suit, and his streamlined muscles are not only aesthetically pleasing, but also contain a power that is no less than that of Barrett.

After developing the gravity field seven months ago, the group's strength has grown remarkably.

Roy can now cover his entire body with Armament Haki, but his swordsmanship hasn't improved much. He can only attach his abilities when slashing, and he's still clueless about how to enter the realm of a master swordsman.

With the support of mental power, Conqueror's Haki possesses even greater suppressive and destructive power.

With our current strength, dealing with ordinary lieutenant generals is no problem at all.

Tesoro has also mastered the Six Powers of the Navy, and his dual-color Haki has awakened under Roy's guidance. Although it is sometimes effective and sometimes not, as long as he continues to train at his current level, he will soon be able to use it proficiently.

Stella, on the other hand, continued to develop the combination of her Devil Fruit ability and the Six Powers of the Navy, forming her own fighting style. The awakening of her Observation Haki made her more sensitive to changes in the surrounding magnetic field and weather.

What surprised Roy the most was Savi. Despite the high intensity of the training, the little guy persevered and his strength increased the fastest among them.

When Roy developed gravity training, Barrett tried it a few times and his visits became more frequent.

After Roy taught him the domineering training method early on, his strength was much greater than that of the same period in the original work, and he was known as the devil's heir on the battlefield!

After spending a lot of time with Roy and the others, Barrett was no longer the sour-faced person he had been when they first met. He would occasionally talk to them about what was happening in the army, and he took the most "care" of the little guy, Savi.

In his explanation, he feared that Savi, following Roy, would be too weak in the future and would be killed when encountering enemies.

However, recently, after arriving, he reverted to his initial state, only now, under Roy's triple gravity, he mechanically performs what can only be described as self-torture—push-ups, squats, hitting giant logs...

Exhausted, they quietly withdrew from the camp and returned to their military quarters.

This scene was witnessed by everyone, and Roy knew that he had been betrayed by his colleagues again.

"Boss Barrett, he..." Tezzolo said with some concern.

"Don't worry about Tesoro. The time for him to make a decision is approaching. We can just wait," Roy said slowly, watching Barrett leave in silence.

"What decision would you make if your loyalty were betrayed by your country? The Devil's Heir, Douglas Barrett!!!"

......

Meanwhile, in the central conference room of the military camp, a man in his forties with a sinister face, Douglas Gray, was assigning tasks for the next phase of the operation. When he glanced at Barrett, who was looking distracted in the corner, a cold glint flashed in his eyes on his already sinister face, but he quickly concealed it.

"Colleagues, this time we will launch a full-scale offensive to utterly defeat the other two nations and end the centuries-long war on this island. At that time, you will all become nobles of this country and enjoy immense power."

The entire conference room suddenly became lively, with the generals reveling in the power and wealth they were about to gain.

Barrett, after accepting his task, silently left the meeting room.

Unbeknownst to him, a sinister gaze lingered behind him as he left.

After the meeting.

"General, Barrett's recent movements are suspicious, and... his strength has increased far too rapidly in the last six months."

General Gray's trusted advisor reported to him after everyone had left.