Shiro had a specific reason for his sudden strike on Impel Down.
He couldn't rule out the possibility that, in the future, the World Government might use some special means to control the monstrous prisoners and launch a suicidal attack on Central Authority.
It wasn't beyond reason to assume the World Government had the means to control the prisoners held there. Shiro believed that, with the methods available to the World Government, they could very well achieve such a feat. If even a strong figure like Bartholomew Kuma, one of the Seven Warlords of the Sea, could have his consciousness stripped away to become a toy slave of the Celestial Dragons, then controlling some prisoners wasn't far-fetched.
Knowing the nature of the Celestial Dragons, if they ever truly felt threatened by the power of Central Authority, they would undoubtedly resort to the dirtiest and cruelest of tactics. That's why Shiro had to act first and eliminate these monsters!
For the prisoners on the upper levels of Impel Down, Shiro had tasked Domino and Little Sadi with carefully verifying their backgrounds. Those who were wrongly imprisoned by the Navy or the World Government, or who were locked up for offending the Celestial Dragons, were given two choices: join Central Authority to fight for the new order or leave and return to their former lives.
However, for the true criminals, like pirates imprisoned for massacring towns, the outcome was simple: death!
No more keeping them locked up. These pirates would face execution, with Roronoa Zoro acting as the chief executioner. Before long, Impel Down was filled with the corpses of pirates who once reveled in pillaging and slaughter. They had finally paid the price for their sins in blood and life!
During the war at Marineford, Shiro had wanted to deal with these scum already, but the situation back then was too complicated to finish the job.
As Zoro executed the pirates, using them as targets to sharpen his swordsmanship, Shiro and Hawk Eyes Mihawk descended to the lowest level – Level 6: Eternal Hell.
Despite Blackbeard's earlier infiltration, which caused some monsters to escape, many of the most notorious criminals were still imprisoned in Eternal Hell. Among them were two notable individuals: Crocodile and Jinbe, the Knight of the Sea.
When Shiro had captured Monkey D. Luffy, the Impel Down breakout attempt had been swiftly suppressed by Magellan. As a result, Crocodile and Jinbe were thrown back into Eternal Hell under strict surveillance. Shiro had plans to recruit these two, provided they were smart enough to see the opportunity.
When Shiro and Hawk Eyes Mihawk appeared outside their cells, Crocodile and Jinbe were genuinely shocked. They had no idea what had happened in the chaos above.
Eternal Hell was the deepest part of the undersea prison, and the tumult above hadn't reached them. The two were still wondering how outsiders had managed to infiltrate Eternal Hell—and not just any outsiders, but Shiro, the man who had destroyed Marineford, and the world's greatest swordsman, Hawk Eyes Mihawk!
While Crocodile and Jinbe didn't always have access to newspapers, they had certainly heard of Shiro's exploits during the war at Marineford. But why were Shiro and Mihawk here together? Had Shiro joined the World Government and become one of the Seven Warlords of the Sea? That didn't seem likely. And even if he had, wouldn't someone like Magellan or even an Admiral be watching them closely?
But right now, there were only these two!
Something was definitely off, and Crocodile and Jinbe quickly sensed it. For them, a break in the norm could mean opportunity—the chance to escape this hellish prison.
"Crocodile, Jinbe, it's good to see you both. Allow me to introduce myself—I am Shiro, Supreme Commander of Central Authority," Shiro said calmly as he looked at the two prisoners.
It seemed the prisoners in Eternal Hell hadn't been getting any news lately. Understandable, considering all the major headlines recently had been negative for the World Government. They couldn't afford to give these powerful criminals any hope or encouragement.
"Central Authority? What kind of joke is that? Never heard of it," Crocodile replied, his usual indifferent attitude unchanged as he sized up Shiro.
This young man had supposedly caused chaos during the war and destroyed Marineford? Impossible! No way a kid this young could possess the strength to destroy Marineford in a battle of that scale. That kind of power was reserved for someone who could rival an Admiral!
"Hey, Hawk Eyes! What are you doing here with this brat? Did you two sneak in? Aren't you afraid of retaliation from the World Government?" Crocodile asked, clearly more interested in Mihawk than Shiro.
"Crocodile, let me remind you—choose your words carefully. If you anger this 'brat,' you might regret it," Hawk Eyes Mihawk said coldly.
Then, under Crocodile's darkening gaze, he continued,
"Also, I'm no longer one of the Seven Warlords of the Sea. I'm now a cadre of Central Authority… under this young man."
Crocodile: "...?"
Jinbe: "..."
For a moment, both men were completely stunned.
They hadn't misheard, had they?
Hawk Eyes Mihawk, the world's greatest swordsman, had joined Central Authority?
And the young man in front of them was the supreme leader of Central Authority?
Hawk Eyes Mihawk had become someone's subordinate?
Just what in the world had happened while they were locked away in Impel Down? What had they missed?
"Crocodile, Jinbe, I won't waste time. I need you both to join Central Authority and help me establish the new order."
...
While Shiro was executing his plan at Impel Down, Zephyr, Aokiji, Fujitora, and Enel, among other key figures, led Central Authority's fleet to launch operations across the first half of the Grand Line, targeting Navy branches.
In the Calm Belt, near Amazon Lily, Central Authority's base, a pirate ship quietly approached the island of the Kuja Pirates.
"Zehahahaha!"
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The fanfic is finished on p@treon/tambeerg