Sean had introduced the concept of the airplane to Retes long ago. However, Sean was no professional; he couldn't explain the nuances of aerodynamics, nor did he know the specific equations for lift.
Consequently, Retes and his team had to start from absolute zero. It took over a year of trial and error before they finally constructed the first airplane in the world of pirates.
It was a simple biplane, completely devoid of weaponry. Its sole purpose was to prove that flight was possible. Even if it failed, the Marine chosen as the test pilot was unlikely to lose his life; his Doriki was over 1,800, and he was a master of the Six Powers, using Moonwalk was second nature.
Watching the plane take to the skies, Sean felt a sense of satisfaction, even if the aircraft looked like an antique to his eyes.
Every great journey begins with a single step. Now that Retes and his team had mastered the fundamental principles, future development would accelerate rapidly. As Sean had noted before, the world of pirates never lacked brilliant scientists—their "tech tree" had simply been developed in the wrong direction. Once given a spark of inspiration, no matter how simple, it was enough to broaden their horizons and allow them to realize those ideas with startling speed.
Biplanes, monoplanes, and eventually, jet engines... Sean believed that following today's successful test flight, these inventions would emerge in quick succession.
'''
One month later.
On a nameless island in the New World, located far from the territories of the Marines or the three Great Emperor fleets, a group of infamous pirates had gathered.
Present were Shanks, Beckman, Charlotte Linlin, Katakuri, Kaido, and King. The six men sat facing each other, divided into three groups.
"Alright, Red-Haired brat, speak up," Big Mom said bluntly. "What exactly is the point of this little gathering you've called?"
"That's right," Kaido added with a sneer. "Don't think that just because you carry the title of an Emperor of the Sea, you're on equal footing with us. If you can't give me a damn good reason why I traveled all this way, I'll kill you where you sit!"
Right from the start, Big Mom and Kaido were remarkably uncourteous. In their eyes, they and Whitebeard belonged to the same era, whereas Shanks was still a mere youngster, regardless of his actual strength. To them, it was absurd that a "brat" would demand their presence. To an outsider, it would seem as if Shanks were the most powerful of the three Emperors, capable of barking orders at the other two.
This rubbed Big Mom and Kaido the wrong way. In fact, they hadn't intended to come at all. Their initial responses were identical: if Shanks had something to discuss, he could come to their respective strongholds.
But then, Shanks had pivoted to threats. He declared that anyone who failed to show up would find the Red-Haired Pirates declaring war on them.
Under normal circumstances, neither Big Mom nor Kaido would have cared. Let them declare war; who was afraid of whom?
But the situation had changed. The New World Marine was currently circling like vultures. If a war broke out between the Emperors, even if one of them emerged victorious over the Red-Haired Pirates, the losses would be catastrophic. They would be left severely weakened, leaving them ripe for the New World Marine to swoop in and finish them off.
Of course, traveling to Shanks' territory was also out of the question. After extensive negotiations, the three parties finally reached a compromise. The meeting was set for an uninhabited island that belonged to none of them.
What they didn't know was that thanks to Princess Violet, Sean was fully aware of their every move. Furthermore, Sean had decided that a meeting of this magnitude was far too interesting to miss.
However, Sean had no intention of charging onto the island. Even for him, dealing with three Emperors clashing in one place would be a tedious headache. Instead, Sean chose a different approach—one that would not only inflict losses upon them but utterly shatter any chance of a successful alliance.
At this moment, the three Emperors remained blissfully unaware.
"I asked you both here today to discuss the issue of the New World Marine," Shanks began. "I believe that after the last battle, you both realize that none of us, acting alone, can withstand Sean and the New World Marine under his command."
"Or are you planning to just sit around and wait for Sean to come and pick us off one by one?"
The mention of the topic caused Big Mom and Kaido's expressions to sour instantly. It was true; the pressure exerted by Sean and the New World Marine was immense.
The previous encounter had been particularly galling. Sean hadn't just launched sneak attacks on their home bases; he had also ambushed their main forces on their way back, inflicting massive casualties. Worst of all, while the two of them had spent months fighting a brutal war of attrition, Sean had simply stepped in and snatched the prize. Now, the entirety of Whitebeard's former territories were held firmly in the grip of the New World Marine.
And they... had gained absolutely nothing.
It was the greatest loss they had suffered since becoming Emperors of the Sea. It was an utter humiliation.
Yet, they were powerless. Having suffered such losses, neither of them had the strength to seek revenge against Sean. It would be a miracle if Sean didn't take the opportunity to attack them now.
"So, what exactly are you proposing?"
"An alliance! We form a Pirate Coalition!"
"A coalition? Bullshit!" Kaido roared, slamming his fist into a nearby boulder and shattering it into dust. "Red-Haired, have you fallen so far that you've forgotten the dignity of an Emperor? You want us to huddle together for warmth like some low-life, third-rate pirates?"
Big Mom didn't explode like Kaido, but her dark expression made it clear she was equally furious. While she had collaborated with Kaido several times, those were temporary arrangements—not some cursed "alliance."
Emperors had their pride. In their eyes, "coalitions" were things created by the weak and the insignificant. Did they, the mighty Emperors of the Sea, really need to resort to such methods for self-preservation?
Ridiculous!
"And so?" Shanks countered calmly. "You're both prepared to let your 'pride' lead you to the slaughterhouse? Or are you truly confident that you can wipe out Sean and the New World Marine on your own?"
Shanks looked at the suddenly silent Big Mom and Kaido. He knew they were wavering.
It was time to add some fuel to the fire.
"Tell you what," Shanks said. "I'll propose this in a way that's easier for you to swallow."
"We aren't looking to form a pirate alliance; we are going to unify every single pirate force in the New World!"
"From this point forward, the three of us will rule together. Every pirate in the New World will be brought under our banner, operating under our collective command!"
"How does that sound?"
Big Mom and Kaido both fell into deep thought upon hearing this proposal.
By rough estimates, there were approximately 1,500 pirate crews scattered across the New World. Of course, this figure referred only to the independent crews, excluding the territories of the Three Emperors. After all, the combined territories of the Three Emperors only covered about twenty percent of the New World's waters.
This meant unifying the entire New World—bringing those 1,500 crews and hundreds of thousands of pirates under their direct control. The three Emperors would essentially become a counterpart to the Five Elders, jointly ruling over a terrifyingly massive force.
It had to be admitted—the idea was incredibly tempting.
'''
Five hours later.
The summit of the Three Emperors concluded. Aside from the vice-captains involved in the meeting, no one knew the details of what had been discussed. However, judging by the expressions on Big Mom and Kaido's faces, the negotiations seemed to have gone well.
Shortly after, the three boarded their respective ships and began their journeys home.
A day later, just as Big Mom was approaching the borders of Totto Land, a Marine fleet suddenly appeared before her. Simultaneously, Kaido was also intercepted by another Marine fleet on his way back.
Almost immediately, both were subjected to a fierce artillery barrage. The accompanying ships were sunk one after another!