As night fell, Hei Yan approached Mio with a pirate in his grasp. "Master, this guy knows the sea area where the rising current is located."
Mio stroked his chin, a satisfied smile spreading across his face. "Good. Have him find a ship to take you there. Once that's done, make sure to remember the location."
He glanced toward the harbor, where the pirates were still hard at work reinforcing his ship. With the pace they were working at, it would take no more than a day before everything was finished.
Then, they could set off.
Hei Yan nodded and left to carry out the order.
Suddenly, Mio slapped his forehead lightly and looked toward the forest behind Demon Valley Town. Something had crossed his mind. "Ah, there are birds in that forest. Might be worth catching a few."
He was referring to the Nan Nan Tori, the bird that Luffy caught in the original story—famous for its ability to always point south. Whether on land or sea, it remained reliable in giving directional orientation.
"If I bring one along, it'll make navigation much easier. Less chance of getting lost," Mio muttered.
There were other birds similar to the Nan Nan Tori: the Kita Kita Tori, Xi Xi Tori, and Dong Dong Tori, each named after the direction they pointed to—north, west, and east respectively. They were curious creatures. Having all four on board would be helpful for navigation and add a bit of fun to their journey.
That said, Mio wasn't personally interested in catching birds, so he decided to let Lilith take care of it.
"I'll just stay here and drink while supervising the ship repairs," he smirked.
After explaining the appearance and traits of the Nan Nan Tori to Lilith, she agreed easily and flew toward the nearby forest of Gaya Island.
Gaya Island was part of the larger Sky Island—Skypiea. It was located near Mogu Town, making it an easy trip for someone like Lilith who could fly.
Time passed quickly.
In the blink of an eye, a full day had gone by.
During that time, Hei Yan had memorized the location of the rising current, and Lilith had successfully caught a Nan Nan Tori. Unfortunately, the other directional birds were not found in the forest.
By dusk, the ship was fully reinforced.
One of the pirates, drenched in sweat, approached Mio. "Captain Mio, according to your instructions, the ship has been reinforced, and the wings have been installed. Would you like to inspect it?"
Mio turned to look at the ship. A thick layer of reinforcement covered the hull, and the newly added wings were spread wide. It matched exactly what he had envisioned.
"No need to inspect it. Looks good," he said with a satisfied nod. "You can go."
The pirate immediately bowed and, after instructing the other shipbuilders, quickly left with his crew. The pirate group they belonged to didn't want to remain in contact with Mio any longer than necessary.
With the repairs complete, Mio and his crew returned to the ship.
A large birdcage had been set up on the deck. Inside stood the Nan Nan Tori, quiet and calm.
It wasn't exactly a cute bird. Its head resembled that of a fish, which made it look quite strange. But Mio didn't care about aesthetics—only usefulness.
"Captain, can we go to Sky Island next?" Robin asked, eyeing the reinforced ship.
"That depends on our luck," Mio replied, casually teasing the Nan Nan Tori with his finger before shrugging. "There are several upwelling currents each month, but the timing is unpredictable. We'll have to wait in the area and stay alert. The current might appear tomorrow—or in a few days, maybe even half a month later."
"Looks like we'll be stuck here for a while," Robin noted.
Lilith and the others were buzzing with curiosity at the mention of Sky Island. An island floating in the sky—it stirred the imagination.
"Even if it takes a while, it'll be worth it," Mio said, his tone full of anticipation. Sky Island held not only a Poneglyph, but also the legendary City of Gold—Shandora. And although there was no guarantee that the Thunder Fruit (Goro Goro no Mi) was still there, the gold alone made it worthwhile.
This time, even if he couldn't get the fruit, Mio was determined not to leave without the gold.
Night descended fully.
Erica went to prepare dinner, and Mio began steering the ship toward the sea area where the rising current would appear.
Soon, the ship reached the designated location under the cover of darkness.
Mio sat cross-legged at the bow and called out, "Hanba."
A moment later, Hanba, the enormous sea beast under Mio's command, surged from the depths with a thunderous splash. The Nan Nan Tori in its cage panicked and covered its head with its wings, clearly startled.
"Master," Hanba rumbled respectfully.
Mio reached into his pocket, then vanished and reappeared atop Hanba's massive head with a simple thought.
"Sky Island is too high up—you won't be able to follow. You'll need to wait for us here on the Grand Line." He took out a Life Card and handed it over. "When we come down, it might not be in this area. Use this to find us."
"Understood," Hanba said, delicately pinching the tiny Life Card and placing it in his mouth.
Hanba had a habit of storing things in his mouth—he'd spit it out when needed.
With that done, Mio returned to the ship and resumed his training.
He focused on his Observation Haki and the powers granted by the Replacement Fruit.
His Observation Haki was fully activated. Holding a handful of peanuts, Mio began flashing across the deck, repeatedly replacing his position with various objects through the fruit's power.
Finally, he gazed at the clouds above and attempted to replace himself with one of them.
But nothing happened.
It wasn't that he couldn't do it—it was just that his ability hadn't developed enough to reach that level.
Still, Mio could feel it was within reach. Replacing clouds wouldn't require a massive leap in power, just a bit more proficiency and control.
He was incredibly eager to explore the full potential of the Replacement Fruit.
Replacement…
If there truly were no upper limits, then his imagination could run wild. It should be possible not just to replace himself with objects, but eventually to make two objects swap places—or even two people.
Abilities… memories…
"Could I one day swap the abilities of two people?" Mio pondered. "Or their memories?"
Though the latter seemed far-fetched, he guessed such feats might become possible after the fruit awakened.
In his mind, Mio divided the Replacement Fruit's potential into stages:
Stage One: Replace himself with inanimate objects.
Stage Two: Replace inanimate objects with one another.
Stage Three: Replace living beings.
And beyond that…
Awakening—a mysterious final stage, with unimaginable power. He had no idea how far he could go or what the true limits were.
But Mio knew one thing: the stronger a Devil Fruit's potential, the harder it was to awaken.
Shaking off the thoughts for now, he took a deep breath.
No point in dreaming too far ahead.
He focused and continued his training under the moonlit sky, determined to master the abilities he had now—until the day the current finally came to take them to the skies.