The Marine Genius Imprisoned in Impel Down

Level Six of Impel Down.

In a solitary cell.

A young man with black hair slowly opened his eyes.

He looked to be around eighteen or nineteen years old, dressed in a striped prison uniform. Heavy Sea Prism Stone shackles restrained his wrists and ankles.

Ever since the Golden Lion broke both his legs and escaped over a decade ago, Impel Down began placing shackles on extremely dangerous criminals.

A person might still be able to fight without legs, but without legs and hands, it's impossible.

Clearly, this young man was considered extremely dangerous.

He slowly moved his neck, producing a series of cracking sounds.

Sitting up from the ground, he leaned against the cold wall and stared blankly at the ceiling.

His name was Sanders, a former Marine Rear Admiral.

It had been 19 years since he was reincarnated into the world of One Piece.

He became an orphan at a very young age and was later adopted by a Marine.

At 14, he finally received the long-awaited gift—a special ability known as the "Power of Derivation."

As the name suggests, he could derive anything.

Without consuming any resources, he could derive techniques, Haki, combat styles, and even various Devil Fruit powers.

However, this ability was not without limitations.

The more complex and mysterious the thing he wanted to derive, the more time it would take.

Moreover, he could only derive one type of ability at a time.

For instance, he could only derive one Devil Fruit power at a time.

He couldn't derive two Devil Fruit abilities simultaneously.

The good news was—he could possess multiple Devil Fruit abilities without exploding.

After all, he hadn't really eaten the Devil Fruits.

Though seawater and Sea Prism Stone could suppress him, the effect wasn't too significant.

He could even use some of his abilities while in the ocean.

For example, he couldn't derive both Armament Haki and Observation Haki simultaneously; it had to be one after the other.

If the derivation process was interrupted, he could switch to something else. The progress wouldn't reset.

It was like downloading a movie online; you could pause and resume whenever you wanted.

Just like how downloading with a premium membership speeds things up, derivation could also be accelerated.

The closer he was to what he wanted to derive, the faster and easier the process.

For instance, if he wanted to derive Armament Haki, it might take him a year of relaxing at home to develop basic Armament Haki.

But if he were near someone proficient in Armament Haki, it might take only half a year.

Training under a strong mentor, sparring, or observing battles would also speed up the derivation process.

Considering the dangers of the One Piece world, and with his adoptive father being a Marine, Sanders decided to join the Marines to grow stronger.

The Marines had plenty of strong people to teach him.

The former Admiral Zephyr, in particular, had various skills that could accelerate his derivation process, such as Armament Haki, Observation Haki, combat techniques, and more.

To make himself more valuable to Marine Headquarters, he joined Zephyr's elite training camp.

The first ability he chose to derive was the Goro Goro no Mi (Rumble-Rumble Fruit).

A powerful Logia-type fruit would ensure that Marine Headquarters noticed him, making it easy for him to join Zephyr's camp.

The Goro Goro no Mi also matched his aesthetic preferences.

Thankfully, he had received a beginner's survival gift pack that gave him an instant derivation ability.

Otherwise, it would have taken him at least five years to derive the Goro Goro no Mi, given how far away Skypiea and its users were.

What followed was smooth sailing.

He joined the Marines successfully and became a member of Zephyr's training camp.

Thanks to his derivation ability, within just a year, he mastered the Six Powers of the Marines, Armament Haki, and Observation Haki.

His talents shocked all of Marine Headquarters.

He was hailed as the most gifted person in hundreds of years, alongside Akainu, Kizaru, and Aokiji—the four "Monsters" of the Logia-type Marines!

(Smoker wasn't included!)

Using the credit he earned from defeating pirates in the first half of the Grand Line, he quickly became the youngest Marine Rear Admiral.

For a time, the Marines dominated the headlines.

Many pirates were so terrified of the four Logia-type Marine monsters that they didn't dare to act out.

Unfortunately, good times don't last.

A year later, while on a mission in the Sabaody Archipelago, his adoptive father was heartlessly shot and killed by a Celestial Dragon while trying to protect a civilian.

Having lost his only family, Sanders couldn't stand it any longer.

He immediately planned to kill the Celestial Dragon in revenge and defect from the Marines to become a pirate.

Before he could act, the World Government charged him with "plotting to harm the World Nobles and betraying the government," ordering Fleet Admiral Sengoku to arrest him.

To prevent Sanders from escaping with his Goro Goro no Mi powers, the World Government sent Kizaru, the user of the Pika Pika no Mi (Glint-Glint Fruit), along with CP0 to oversee the mission.

At that time, Sengoku was about to be promoted to Fleet Admiral, and Kizaru was set to become a Marine Admiral.

In other words, Sanders had to face two Admiral-level opponents simultaneously.

Thinking about this still made him angry.

One Admiral wasn't enough—they had to send Kizaru as well.

If it had been anyone else, he might have had a chance to escape.

But the World Government was determined not to let him become a pirate.

Despite trying everything, he ultimately failed to escape.

Kizaru's speed was faster than his, giving him no chance to flee.

In the end, he was defeated and imprisoned in Level Six of Impel Down.

Now, it had been three years since his imprisonment.

Taking a deep breath, Sanders mentally opened his panel:

Name: Sanders

Age: 19

Abilities:

Goro Goro no Mi (Awakened!)

Advanced Armament Haki

Advanced Observation Haki

Advanced Conqueror's Haki

Giant's Strength

Advanced Combat Skills

Marine's Six Powers

Life Return

Without exaggeration, he was now Admiral-level!

According to what Sanders knew, the current three Admirals all had advanced combat skills, Haki, and awakened Devil Fruits.

These were the minimum requirements to become a top-tier fighter.

Even Kizaru, who Zephyr criticized for relying too much on his Devil Fruit, had advanced Haki and combat skills.

As for Zephyr, known for his mastery of Armament Haki, his Haki was at the top level.

It was common knowledge that Armament Haki differed in both quality and quantity depending on the person.

Zephyr's Armament Haki was the strongest Sanders had ever seen.

With the same amount of Armament Haki, Zephyr had higher defense and greater attack power than anyone else.

That's why Zephyr's Haki was considered top-tier.

Being in Impel Down had taken away his freedom, but it had also provided him with the nourishment to grow stronger.

The entirety of Level Six was constantly feeding his strength.

That was one reason why he hadn't immediately tried to escape.

Where else could he find so many powerful individuals to fuel his derivation at all times?

Of course, another reason he hadn't tried to escape was that Magellan was too strong.

In the narrow confines of Impel Down, the Doku Doku no Mi (Venom-Venom Fruit) gave Magellan a huge advantage.

Without absolute confidence, Sanders wouldn't attempt an escape.

As for his fruit abilities, the Goro Goro no Mi was the first ability he derived.

After joining the Marines, he spent most of his time developing it.

With the help of the Marines and Vegapunk, his fruit development progressed rapidly.

A year after his imprisonment, he achieved awakening.

The Momo Momo no Mi came from the World Breaker, Byrnndi World.

That man was also a prisoner on Level Six, not far from Sanders, which made it easy to derive his power.

It only took a year to fully derive it, since they were together all the time.

The Giant's Strength came from the later Blackbeard Pirate, Sanjuan Wolf.

As for Haki, his Armament Haki and Observation Haki were at intermediate and basic levels before entering Impel Down.

By leeching off Douglas Bullet, he reached his current state.

Douglas Bullet was truly strong, especially when it came to Armament Haki, which was at the top level.

Unlike Zephyr, Bullet's top-tier status came from the sheer amount of Armament Haki he possessed.

In terms of quantity, Bullet had far more Armament Haki than anyone else Sanders had ever seen.

In the movie, Bullet even covered his gigantic body with Haki.

If Bullet hadn't messed around with his "mecha" in the film, he wouldn't have lost.

The Gasha Gasha no Mi (Fusion-Fusion Fruit) really held Bullet back.

If he had just eaten a random Zoan Fruit, Bullet would have been practically invincible with his Armament Haki alone.

Sanders only developed his advanced combat skills and Life Return after entering Impel Down.

He and Bullet were the only ones in the prison who kept up with their training.

They were often mocked by other pirates for this, but neither of them cared.

They continued to train every day.

Sanders scrolled down his panel with his mind, revealing the abilities he was currently deriving.

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T/N:

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