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

"Haha, another Devil Fruit!"

Roy happily picked up the fruit. "Judging from the color and texture, it's most likely a Paramecia type. I just don't know what kind of ability it has."

I really don't understand why the Giant Axe Pirates didn't eat the Devil Fruits they had; now they've gotten a free one.

Now that I have the Nen-Nen Fruit, and Tesoro is the only one on the ship who hasn't eaten a Devil Fruit, I can leave this fruit to him.

I just don't know what kind of ability it is. What if it's a useless ability that actually limits Tesoro's development?

After all, the future "Golden Emperor" relies on the Gold-Gold Fruit.

"Let's put it away for now, and deal with it after we figure out its abilities or find something more suitable..."

In the days that followed, the pirate ship "White Dove" (proposed by Stella and agreed to by Tesoro) continued its journey toward the land of endless war.

After eating the Bird-Bird Fruit, Stella's perception of weather and magnetic fields has become increasingly acute, and at Roy's suggestion, she has also begun physical training.

Tesoro was like he was on steroids. Apart from helping to steer the ship and learning some navigational knowledge from Stella, he spent all his remaining time training on the deck. His enthusiasm was frightening to watch.

Roy himself wasn't idle either.

He practiced his swordsmanship on the deck during the day. The longsword "Frost and Snow," which he bought from the weapon shop on Maple Leaf Island, sliced ​​through the air in his hands. (The shopkeeper boasted that it was a fine, fast sword, and Roy thought it felt alright in his hand, so he bought it.)

There are no fixed moves; he just wants to figure out how to combine his telekinesis with sword techniques. At the same time, he is researching Armament Haki by combining the principle of the Iron Body from the Six Powers of the Navy.

He would focus on meditation at night, honing his mental strength and developing his fruit abilities. The fine control of his mental strength, the expansion of its range, and the precision and power of his manipulation of objects were all areas of his research.

He even tried to combine telekinesis with Conqueror's Haki. Although progress was slow, the occasional glimpse of his oppressive aura had already made Tesoro and Stella on the ship feel uneasy.

On this day, the sky was azure and the sea breeze was gentle.

Roy finished a round of sword practice and watched Tesoro doing weighted squats on the deck according to the illustrations in the booklet. In just over ten days, Tesoro's muscle definition had become much more obvious, and his eyes had become sharper.

"Tezzolo, come here." Roy beckoned.

"Boss, what are your orders?"

Roy didn't answer directly, but instead looked at Stella, who was adjusting the sails: "Stella, where are we now? How far are we from the Land of Endless War?"

Stella dusted off her hands, sensed the wind direction and ocean currents, and checked the logbook and nautical chart: "Captain, at the current speed and route, we should reach our target area in about five more days. However, we'll need to find out exactly which island the Endless War is located on once we get there."

"Five days..." Roy nodded, his gaze returning to Tesoro. "Your basic physical abilities have improved rapidly; it's time to begin the next stage of training."

Tesoro's eyes lit up with anticipation.

"Boss, teach me quickly!"

Roy extended his finger, a faint wisp of black substance swirling around its tip: "Haki is an essential ability for the world's top fighters. There are three types: Observation Haki, Armament Haki, and Conqueror's Haki. Conqueror's Haki is innate and cannot be trained; you either have it or you don't. But Observation Haki and Armament Haki are powers that exist in everyone's body and can be mastered through training."

He paused, then continued, "Observation Haki allows you to sense presence, predict attacks, and even read others' emotions and thoughts. Armament Haki, on the other hand, enhances your own defense and attack power, and is especially effective at detecting the physical presence of Logia-type Devil Fruit users, making it crucial for dealing with them."

Tesoro was deeply moved and his breathing became rapid.

"My Observation Haki is quite special; after eating a Devil Fruit, I was able to materialize my mental energy," Roy said.

"Now, I will guide a wisp of my spiritual energy into your body, allowing you to experience the feeling of 'perception' for the first time. You must remember this feeling firmly, and then try to capture and activate your own potential for Observation Haki."

As he spoke, Roy gently touched Tesoro's brow with his fingertip.

Tesoro shuddered as a cool, gentle power surged into his mind, and in an instant, the world around him seemed to change. He "saw" the gentle aura emanating from Stella not far away, "heard" the sound of fish swimming beneath the surface of the sea, and could even vaguely sense Roy's calm and focused emotions at that moment.

This wonderful feeling captivated him.

"Remember this feeling!" Roy's low shout echoed in his mind.

Tesoro quickly composed himself and focused all his energy on memorizing and comprehending the information.

A few minutes later, Roy withdrew his finger. Tesoro was momentarily dazed; the strange sensation faded, but it left a deep imprint on his mind.

"Thank you, boss!" Tesoro said excitedly.

"This is just a guide. Whether you can awaken and how far you can go depends entirely on yourself," Roy said seriously.

"Next, spend half of each day calmly sensing your surroundings and trying to regain that state of perception. Spend the other half practicing the Six Styles of the Navy, and then continue to hone your physique. A strong body is the foundation for bearing Haki. As for Armament Haki, I will teach you after your physique becomes stronger, or after you awaken Observation Haki."

"Yes! I will definitely try my best!" Tesoro nodded vigorously, and couldn't wait to run to the side, close his eyes and begin to try to train his Observation Haki.

Stella watched all this with a hint of envy in her eyes.

Roy noticed her emotions and smiled, "Stella, your Devil Fruit ability also has great potential."

"Zoan-type Devil Fruit users already possess excellent physique and regenerative abilities, and their flight and weather perception are irreplaceable. Try combining your perception with your Devil Fruit abilities while flying; you might gain unexpected benefits. There is more than one way to fight."

Stella listened thoughtfully, then smiled and said, "I understand, Captain. I will make good use of my abilities."

After instructing the two, Roy also reviewed his current abilities. As for swordsmanship, there wasn't much to say. He still had no idea how to become a swordsman. He had also managed to draw out Armament Haki from his body with his powerful mental strength, although it was still very weak.

However, telekinesis, enhanced by Observation Haki, can invade the minds of others. In the future, it's not impossible to alter the perceptions of opponents with weak willpower.

In learning the Six Styles, he only chose to practice the Shave move, which is a high-speed movement. What, you mean Life Return is a method that involves infusing the spirit into the body, thereby enabling free control of the body?

Under Roy's immense mental strength, he learned that technique as soon as he saw the training method.

Roy now claims he's terrifyingly strong!

He could even try against a Vice Admiral; even if he couldn't win, escaping wouldn't be difficult. (Garp doesn't count.)

As the sea breeze swept across the deck, watching my two companions begin their respective efforts to become stronger, my anticipation for the endless war country we were about to reach grew even stronger!

"Barrett... I hope you won't let me down," Roy murmured, gazing at the distant sea.