Chapter 40: Recovery and the Lifting of the Healing Seal

When Rosinante saw the method of mastery of "Heart Net" that had been handed over at the temple, he was utterly shocked. This Heart Net turned out to be a training technique for Observation Haki.

In the world of One Piece, whether it's the World Government that has ruled for over 800 years, the top pirate crews across the seas, or the underground organizations—none of them have any systematic methods for training Haki. Most rely solely on experience, repetitive practice, and combat to improve. Rosinante had never heard of any specialized technique manuals for mastering Observation or Armament Haki.

The difference between the two approaches is like external and internal martial arts from his past life.

Although the Heart Net may not necessarily be stronger than traditional training, its very existence represents a different path for mastering Observation Haki.

If one could rely on the Heart Net to research a more advanced method of internally mastering Observation Haki, the improvements it could bring to Rosinante would be immeasurable!

To enhance his Observation Haki, Rosinante had tried countless training methods over the years—some he invented, others inspired by the anime of his past life, and even some derived from knowledge acquired in the information age.

But once his Observation Haki reached its current level, those training methods gradually became less effective.

Now, the only way to enhance it further would be through continuous high-level combat—like how Katakuri, under immense pressure, broke his limits and evolved.

But the emergence of the Heart Net revealed another path to Rosinante—one that could take him to greater heights.

Since Rosinante's strength largely depended on the foundation of his Observation Haki, only by improving that could he further develop his Devil Fruit abilities.

The strength of his Observation Haki was absolutely critical to him.

However, the current version of the Heart Net on Skypiea offered limited help to Rosinante, making in-depth research into it crucial.

To be honest, Rosinante wasn't some kind of genius. The reason he had managed to master Observation Haki to this level was thanks to the strength of his soul and the broad perspective gained from his past life.

To expect him to single-handedly advance the Heart Net mastery method to a higher realm was nearly impossible.

But didn't he now have a true prodigy of Observation Haki under his command?

Katakuri—who had refined his Observation Haki to the point where he could glimpse the future—was a true genius.

In the current One Piece world, no one had greater mastery or talent in Observation Haki than him. Even the Pirate King Roger probably didn't have such achievements at Katakuri's age!

"How interesting—I didn't expect Observation Haki to have such a method of training," Katakuri said.

"This isn't just a training method," Rosinante replied. "It's a refined and layered internal art. If we follow this path and develop a more effective technique, the potential for growth in Observation Haki is incalculable. Even though you can now predict the future, I suspect you're still far from fully mastering it. If we can develop a better internal training method, it'll be a huge help for you in truly controlling that power. So—interested?"

"I'll take it on!" Katakuri nodded without hesitation.

"These are some insights I've compiled about mastering the Heart Net. You might want to take a look." Rosinante handed over a handwritten manuscript.

Katakuri glanced at the manuscript—and his face instantly froze in astonishment.

He had originally thought that Rosinante just wanted to use him to develop a higher-level Heart Net. But after seeing the contents of this manuscript, Katakuri couldn't help but reevaluate him.

The notes were filled with outlandish ideas and deep insights into the philosophy behind the Heart Net—concepts like meditation, the mind being as still as the sky, or as pure as ice, unmoved even if the heavens fell. It was an eye-opening experience for Katakuri.

"With so many insights already, why'd you even come to me?" Katakuri glared at Rosinante, half irritated.

"Well, I have other things to take care of. But if you feel my notes are hindering your creativity, feel free to return them," Rosinante replied with a grin.

What Katakuri didn't know was that none of those ideas came from Rosinante himself—they were simply concepts he remembered from his previous life, which happened to align with the Heart Net. Rosinante didn't have the ability to come up with such deep philosophies on his own.

"Hmph." Katakuri snorted, stuffed both manuscripts under his arm, and turned to leave—off to dive deep into his research on Observation Haki.

Watching Katakuri's retreating figure, Rosinante smiled faintly, then turned to his own training.

After his battle with Garp, the intense pressure had granted Rosinante deep insights—not just into his Devil Fruit powers but also into his physical combat and Haki.

Now he needed to convert those insights into actual combat strength—but that required a stronger foundation.

In truth, Rosinante had hit a bottleneck in his development. To grow stronger, he needed greater stamina and physical power to support the consumption of both his Fruit and his Haki.

While it might seem like Rosinante was already strong—able to defeat Katakuri and even exchange a few blows with Garp when going all out—the reality was more complicated.

Without using extreme techniques like "Body-Sealing Silence," which pushed him to his limits, Rosinante's true strength was only slightly above that of an average vice admiral.

His Devil Fruit was strange and hard to predict, and most people's Observation Haki couldn't fully track his movements. That's why even top-tier vice admirals like Sakazuki would struggle to deal with him.

But if you stripped away his Devil Fruit, relying only on his Haki and physical prowess, he probably wouldn't even match a standard vice admiral. His constitution was more on par with a rear admiral—after all, he was still just a teenager.

Right now, Rosinante heavily relied on his Devil Fruit. All his abilities were developed based on it. Without it, his combat ability would be greatly reduced.

But his Fruit development had also reached a ceiling.

No matter how strange or powerful a Fruit might be, using its abilities required a base level of physical stamina.

And Rosinante's current body wasn't strong enough to support more powerful developments of his Fruit.

In fact, Rosinante had realized long ago that he had reached a bottleneck.

When his Observation Haki became refined enough to sense the life force of living beings, he had once thought about developing abilities that could directly target life essence itself.

If successful, he would gain the power to attack the very nature of living things.

Unfortunately, he failed. The essence of life was like an indestructible stone—no matter how he tried to penetrate it, it remained unmoved and invulnerable.

Rosinante knew that unless he possessed a body as tough as one of the Four Emperors, he wouldn't be able to touch the core of life itself.

In short, his current physical body was too weak to support more powerful ability development. If he wanted to improve his strength, there was no shortcut—he had to train his body hard.

Only by strengthening his body could his Fruit abilities and Armament Haki improve in tandem.

But physical training wasn't something you could accomplish overnight. It required persistent, long-term effort.

And before he could even begin that, he had to deal with a problem—the Healing Seal.

The Healing Seal, ever since its creation, had saved Rosinante's life several times. It was one of the most miraculous powers he'd developed.

But now, it was becoming a shackle on his growth.

Everyone knows that training involves repeated tearing and healing of muscle fibers. It's through this damage and recovery that the body grows stronger and more resilient.

But the Healing Seal completely blocked this process.

Before his muscles could even begin to tear, the Healing Seal would immediately silence all potential injuries. As a result, no real muscle damage occurred—thus, no strengthening followed.

Sure, Rosinante could later forcibly release the sealed injuries, but that kind of retroactive damage didn't yield the same training effect—on the contrary, it could even harm his body.

So, before he could begin serious training, Rosinante had to first completely heal all the injuries sealed by the silence, and then disable the Healing Seal entirely.

"AHHHH!!!" A blood-curdling scream echoed out as Rosinante released the Healing Seal.