One Piece: Deriving All Things

To ensure his daughter Shirahoshi would live comfortably aboard the Thunder God, King Neptune requested modifications to certain rooms on the ship. Sanders was more than happy to agree—after all, if Neptune wanted to spend his own money for his daughter's comfort, Sanders wouldn't object.

Additionally, Sanders utilized his Māji Māji no Mi ability to assist with the renovations. After examining the ship's layout, Neptune decided to allocate the topmost level for Shirahoshi's room. The reasoning was simple: her large size required spacious accommodations, and her timid nature meant she would feel more at ease with some privacy.

Sanders readily agreed. To the Thunder God Pirates, the Thunder God was merely a mode of transport; their true base of operations was the floating island in the sky. If not for the necessity of visiting Fish-Man Island to bring Shirahoshi along, the crew would have flown directly over the Red Line into the New World using their island.

At the Hard Shell Tower, Shirahoshi's room remained largely untouched despite Vander Decken IX's threat being eliminated. However, the doors were no longer kept sealed.

Today marked the day the Thunder God Pirates were set to leave. Neptune oversaw palace maids helping Shirahoshi pack her belongings. In truth, there wasn't much to pack, as everything Shirahoshi might need had already been arranged in her room aboard the Thunder God.

The plan was straightforward: after coating the ship, the Thunder God would leave Fish-Man Island. Neptune would discreetly escort Shirahoshi to the surface before she boarded the ship. This arrangement avoided the bustling port and ensured the islanders wouldn't discover that Shirahoshi, the Mermaid Princess, was joining a pirate crew.

Once everything was ready, Neptune turned to Sanders.

"You may depart ahead of us. I will honor our agreement and bring Shirahoshi to the surface."

"I trust you, King Neptune," Sanders replied with a casual wave.

Before the crew left, Neptune handed Nami a Log Pose.

"As the navigator of the Thunder God Pirates, you will need this for navigating the New World."

"This Log Pose has three needles!" Nami exclaimed in surprise.

"Yes, a single needle won't suffice there," Neptune explained.

Nami compared it to her existing Log Pose and noticed that the needle no longer pointed steadily in one direction.

"Huh? I thought it had already stored the next island's magnetic field?"

"It has," Neptune clarified. "In the New World, magnetic fields are stored much faster—within half a day. In the first half of the Grand Line, you relied on the Log Pose to record the magnetic field of the next island and used that to navigate.

"However, the second half of the Grand Line is different. Ocean currents and weather patterns often change unpredictably, and some islands have magnetic fields that fluctuate wildly. In extreme cases, the magnetic fields may even disappear entirely during your journey.

"With three needles pointing to different islands, you can choose one of three potential routes. A skilled navigator can determine the safest route by observing the subtle movements of the needles.

"In simple terms, the more erratic the needle's movement, the more dangerous the route to that island will be."

Nami listened intently, absorbing the valuable information about navigating the New World.

"Thank you so much, Uncle Neptune!" she said earnestly.

"Hmph, I'm doing this for my daughter's sake," Neptune replied gruffly, though his concern was evident.

Since coming to terms with Shirahoshi's departure, Neptune had carefully observed the Thunder God Pirates. Thankfully, he hadn't noticed any alarming behavior among the crew, giving him a small sense of relief.

After exchanging a few more pleasantries, the Thunder God Pirates returned to the port and boarded their ship. The Thunder God, now fully coated, was ready to set sail.

As the ship departed from the enchanting underwater paradise, it ascended to the surface with the same quiet efficiency it had when diving down. This time, however, the journey to the surface took significantly less time.

To ensure a smooth journey on the surface, King Neptune arranged for a large fish to tow the Thunder God after it emerged from the depths.

The ship ascended to the sea's surface, where the weather was pleasant and sunny. Stretching under the warm sunlight, Nami let out a satisfied sigh.

"It's so nice to be back on the open sea. The journey to Fish-Man Island felt like a dream. I can't believe such a magical place exists beneath the waves."

"Captain," Nami called out, turning to Sanders.

Sanders stood at the bow, facing the sea breeze with a bottle of beer in hand.

"What is it?"

"Where are we heading next?"

Her question drew the attention of the entire crew, all curious about their next destination.

"Our next stop is Dressrosa," Sanders replied calmly. "We'll settle things with Doflamingo and get Law his revenge."

His tone was so casual, it was as if Doflamingo's infamous reputation meant nothing to him.

"After that," he added, "we'll take some time off for training."

"Training?" Nami asked, puzzled. She didn't feel they were in poor condition—why the sudden need for a break?

"You heard me. Training. Right now, most of you are too weak. Many of you haven't even mastered Haki yet. Do you expect to fight the Four Emperors in your current state? What do you want me to do—take on Issho while soloing an entire Yonko crew?" Sanders rolled his eyes.

The Thunder God Pirates were a young crew, most members barely in their twenties. While their youth promised potential, it also meant their abilities had yet to fully mature.

As the captain, Sanders wasn't a babysitter. He couldn't always rush into battle and shoulder every fight, especially against weaker opponents. That would be embarrassing.

Thus, after resolving matters in Dressrosa, Sanders planned to have the crew focus on improving their combat abilities, including mastering Haki. Even he had his own form of training in mind: challenging powerful opponents across the New World to push his limits.

Hearing this, Nami stuck out her tongue playfully, while the others looked visibly ashamed. Compared to members of Yonko crews, they were undeniably weaker. In the New World, even the lowliest grunts were proficient in Haki, yet many of them hadn't even begun learning it.

Their ability to fly in the sky with their ship was their saving grace. Without it, the captain and first mate would be forced to protect the rest during encounters with other pirate crews.

Sanders turned his attention to Trafalgar Law, addressing him directly.

"What do you want, Law? Should I kill Doflamingo for you, defeat him and let the Marines arrest him, or leave him to you until you're strong enough to take him down yourself?"

Law hesitated.

Of course, he wanted to take his revenge personally, but after their crushing defeat on Sabaody Archipelago, he was acutely aware of the vast power gap between himself and Doflamingo. It would take time—time that Dressrosa's citizens didn't have.

He couldn't bear the thought of leaving the island under Doflamingo's brutal rule any longer.

The idea of "waiting until strong enough" was immediately dismissed.

After a brief pause, Law raised his head and looked at Sanders.

"Captain, if possible, I'd like to expose the Donquixote Family's schemes in Dressrosa and have the Marines arrest Doflamingo. For someone like him, spending the rest of his life imprisoned in Impel Down would be worse than death."

"Alright, we'll do it your way," Sanders said with a smile.

He didn't particularly care about Doflamingo's fate. What mattered to him was fulfilling his promise to Law and locating the Tontatta Princess, whose Heal-Heal Fruit ability could potentially be crucial for his plans.

"Why isn't Shirahoshi here yet? Did King Neptune change his mind?" Nami muttered softly, gazing out at the sea.

Just as she said that, the water began to churn violently.

A large shark wearing clothing surfaced, and atop it sat Shirahoshi, curiously observing her surroundings.

The sky, the clouds, the sun... everything on the surface was a new and wondrous sight to her.

"Shirahoshi!" Nami waved enthusiastically, calling out to her.

Hearing the voice, Shirahoshi turned and saw Nami aboard the Thunder God.

"Lady Nami!" she replied joyfully.

At that moment, more sea creatures began emerging from the water.

Riding on one of them, Neptune appeared, looking stern. "Shirahoshi, why did you rush ahead? What if something dangerous happened?"

"I'm sorry, Father," Shirahoshi replied with a pout, her tone pitiful. "It's my first time on the surface, and I got a little too excited..."

Seeing her about to cry, Neptune softened instantly. "Alright, alright, I won't scold you anymore," he said with a smile, trying to comfort his precious daughter.

Soon after, the princes Shark, Ryuboshi, and Manboshi appeared with a group of Fish-Man guards.

Seeing that her father was no longer upset, Shirahoshi happily dove into the water and quickly swam toward the Thunder God.

The ship was enormous, and from the water, Shirahoshi could only crane her neck to look up at the crew on the deck.

"Lord Sanders, how can I get on board?" she asked, seeking help.

Sanders smiled gently and floated into the air.

"More-More • Tenfold Size!" he declared, using the powers of the More-More Fruit.

Under the astonished gazes of everyone, Sanders began to grow larger and larger until he stood over twenty meters tall, like a giant.

"Wow! Lord Sanders became huge!" Shirahoshi exclaimed in amazement.

Robin, Nami, and Issho didn't look too surprised. They had seen Sanders use his powers to enlarge objects before, so they were already aware of his Devil Fruit abilities.

The newer members, including Law, had no idea.

"Is this a joke? How did the captain grow so big?"

"Wait, is the captain secretly a giant?"

"This must be the power of a Devil Fruit!"

"But isn't the captain a Rumble-Rumble Fruit user? Does it allow you to grow bigger too?"

Penguin and Shachi were left dumbfounded, muttering among themselves.

Not far away, Neptune and the others were equally stunned.

Once Sanders had grown to his full size, he floated down to Shirahoshi, reached out his massive hands, and gently lifted her from the water. Then, carrying her carefully, he brought her onto the deck.

For some reason, seeing Sanders hold his beloved daughter like that made Neptune's heart clench painfully, as though he were losing something precious.

He shook his head, attributing the feeling to the sadness of parting.

"Wyper, lower some planks or ropes and let the others climb up themselves," Sanders instructed as he returned to his normal size.

Carrying Shirahoshi was fine, but as for the other Fish-Men, whose appearances varied greatly, Sanders felt he'd rather face all the Yonko at once than handle that.

"Wow, Captain really plays favorites!" Nami teased with a smirk.

Robin chuckled, covering her mouth.

"Yes, Captain!" Wyper replied, promptly ordering the Thunder Guard to lower ropes.

One by one, ropes were dropped into the water, and Ryuboshi led twenty Fish-Man guards onto the ship.

"Shirahoshi, take good care of yourself," Neptune said with teary eyes as he watched his daughter board the ship, unable to hold back his emotions any longer.

"Alright, it's not like you won't see her again," Sanders remarked casually.

"And isn't that what Den Den Mushi are for? You can call her ten times a day if you want," Sanders casually said to Neptune.

"Take good care of your sister," Neptune ignored Sanders and addressed his second son, Ryuboshi.

"I will, Father! I promise that nothing will happen to Shirahoshi!" Ryuboshi declared firmly.

Finally, Neptune looked at Sanders and said, "Take care of Shirahoshi."

"Got it," Sanders replied simply.

Once everything was ready, the Thunder God set sail again.

To prevent Neptune from following them in a desperate attempt to stay close to his daughter, Sanders had the Thunder God take to the skies, soaring away.

"Wow! The ship is flying! Can all ships fly?" Shirahoshi exclaimed in amazement as she stood on the open deck, watching the sea grow smaller beneath her.

"Only our ship can fly. Other ships can only sail in the water," Nami explained with a proud smile.

The pride in her voice was evident—the only ship on the seas that can fly.

"That's amazing! The Thunder God Pirates are incredible!" Shirahoshi cheered excitedly.

"Not you Thunder God Pirates—we Thunder God Pirates. You're part of us now," Nami teased, correcting Shirahoshi's phrasing with a playful smirk.

"Ah?" Shirahoshi blinked, looking confused.

"I'm... a pirate too? What do pirates do?"

"Do I have to act fierce?" Shirahoshi furrowed her brow and tried to look intimidating, but her adorable attempt only made Nami and Robin burst into laughter.

The sound of their joyful laughter filled the air, bringing a smile to Sanders' face as he listened from a distance.

He opened a panel and checked a specific entry:

[Currently deriving the Sea King Power of the Mermaid Princess Shirahoshi. Estimated time remaining: 1 year, 358 days, and 17 hours.]

It had been several days since Sanders began working on unlocking the Sea King power. To fully acquire it would still take almost two years.

However, one thing made Sanders uneasy. The power of Poseidon—Shirahoshi's ability to communicate with and command Sea Kings—was a formidable force.

What if, when the time came, the Sea Kings rejected him because he was human and male?

Rejection would be one thing, but what if they outright attacked him?

He considered using his Super-Super Fruit to imitate Shirahoshi's appearance if necessary.

After some thought, Sanders decided not to dwell on the matter.

After all, Shirahoshi was now a member of his crew, and he could address the issue later.

Putting that aside, Sanders began contemplating his next steps.

Currently, he possessed the Rumble-Rumble Fruit and the Ice-Ice Fruit—two powerful Logia abilities. He also had the Float-Float Fruit, Fusion-Fusion Fruit, and More-More Fruit from the Paramecia class.

The Heavy-Heavy Fruit was nearing completion, with just over two months left to unlock.

A sparring match with Issho would likely allow him to fully acquire that power.

Of all his Devil Fruit abilities, the Rumble-Rumble Fruit and Float-Float Fruit were the most fully developed. The others were still in their early stages of use.

What he lacked now was a powerful Zoan-type ability.

Zoan fruits, especially Mythical Zoan, would provide significant boosts to physical strength and defense. With one of those, Sanders was confident his strength would rise to an entirely new level, making him fearless in one-on-one combat against anyone in the world.

If he could achieve an awakening, there would be no doubt—he would become the world's strongest being, surpassing even peak Whitebeard and Pirate King Roger.

With that in mind, Sanders decided that after their mission in Dressrosa, he would focus on challenging Kaido.

In the process, he could also test his strength against the other Yonko.

While the rest of the crew focused on training, Sanders would travel the seas, seeking battles and opportunities to find more Devil Fruits to enhance his crew's power.

Having organized his thoughts, Sanders headed to the deck.

There, Law and the others were practicing martial arts under Issho's supervision, with gravity being applied to increase the difficulty.

Sanders joined in to experience the effects of the Heavy-Heavy Fruit firsthand, speeding up its derivation process.

Seeing their captain, a top-tier powerhouse, also training diligently, Law and the others pushed themselves even harder.

If someone who could defeat Admirals was still training so intensely, what excuse did they, as weaker members, have to slack off?

Soon, the entire ship was filled with the sound of vigorous training and determination, creating an atmosphere of unyielding resolve.

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T/N:

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