Grand Line, Calm Belt.
The sky was a flawless blue, without a cloud for miles.
The sea was as still as a pool of dead water, with not the slightest sea breeze passing over its surface.
After a medium-sized blue warship passed through the special rapid currents of the Gates of Justice, its sails went slack, losing their wind power.
Immediately afterward, the warship activated the Jet Dials from Sky Island installed at its stern, as well as the paddle-wheel devices along both sides of the hull, and began speeding across the calm, wave-free sea.
After quite some time, Sephiroth, standing at the bow, finally spotted a ring-shaped prison fortress at sea surrounded by twenty warships... Impel Down!
The prison could be divided into an outer ring and an inner ring, connected only by a drawbridge. Inside was an extremely tight security system, equipped with numerous surveillance Den Den Mushi and various powerful Jailer Beasts, earning it the title of an "impregnable fortress."
Impel Down was divided into six levels from top to bottom. The lower one went, the stronger the prisoners held there became. On the sixth level were even terrifying criminals who had committed monstrous crimes.
If these people escaped into the outside world, they would bring enormous turmoil and unrest to the entire world!
After the warship docked at Impel Down's main entrance, Sephiroth, Domino, Akainu, and Aokiji descended the gangplank.
Although Sengoku had agreed to let Sephiroth personally kill Bondi Walde in Impel Down, he had still sent both Admirals Akainu and Aokiji along.
Clearly, Sengoku was guarding against him!
Rumble!
As Impel Down's iron-bar gate inlaid with Sea Stone slowly rose, two enormous wooden doors opened as well. A middle-aged man five meters tall, dressed in black, with Black Wings on his back and two