As they dove further down into the abyss, Luffy and Zoro considered the idea of trying to catch the schools of fish that swam past, only to be met with several blows to the head from Usopp and Chopper for their idiocy. Sanji had a complete meltdown over Nami's beauty, knocking him unconscious due to severe bleeding from the nose. With him out of commission, Luffy suggested they have a picnic with the food provided to him by Boa.
As they ate, Franky told the story of how Kuma protected the ship after Duval and Hatchan were defeated by the Navy, and how even though his personality was now entirely gone, the man who oversaw his conversion into a machine, Dr. Vegapunk had programmed orders into his brain to protect the Sunny until a Straw hat returned to claim it.
"Suddenly I find myself grateful that I never tried to kill him back at Marineford," said Itachi. "Seems we all owe Kuma a great debt."
Unfortunately, Caribou and his brother, who were involved in the fight between the Navy and the Fake Straw Hats, followed them down, ramming the sides of their ships together so he could board them. Fortunately, Caribou is wildly incompetent, and the Mohmoo pulling his ship along was the same one from Arlong Park, and it therefore fled at the mere sight of Luffy and Sanji. This left Caribou as the only person from his crew on board the Sunny, and was very quickly reduced to begging for his life.
Itachi, however, wasn't having it. "Captain, I recognize him from the Wanted posters at a cafe that Robin and I stopped at back on Sabaody. His name is Caribou, and he's worth two hundred and ten million berries. I could use my Transformation Jutsu to walk right into the next Navy base we come across and collect on it."
Nami, whose eyes had turned into berry signs, was a big fan of that idea. "Yes, please! Two hundred and ten million sounds like a great payday for so little effort!"
Eventually, they caught a deepsea current to take them deeper down, and as the temperature decreased, the girls donned their winter coats to keep warm. The kraken soon made its presence known, and Luffy had the bright idea of taming it so they could use it to pull the ship along. He, Zoro, and Sanji headed out in smaller dive suits made of the same coating that protected the ship, allowing them to fight freely. Unfortunately, they forgot the safety ropes.
"Damn those three!" exclaimed Itachi, tying a rope around his waist. "We're still riding the current; I need to go get them before we get separated!"
Unfortunately, by the time he was able to get secured and get out into the water, the current was already dragging the ship away. He even went so far as to use his Susano'o to extend his reach, but he just barely missed grabbing them before the rope lost all its slack, and he was pulled under with the ship.
It took a few minutes for the rest of the crew to reel him in, and by the time he got back on board, Luffy, Zoro, and Sanji were well out of sight. Caribou had also escaped the ropes they'd used to bind him, and hid in a barrel, which Franky tied and nailed shut upon discovering him. They spent the next several minutes dodging gigantic sea creatures, being forced to repeatedly use the Coup de Burst which steadily depleted their air supply. Eventually, they stumbled into a bed of undersea volcanoes. In their attempt to escape, they were intercepted by a giant anglerfish, who was reprimanded by a giant… person? For attempting to eat them.
From behind the person, a decrepit-looking ship bearing the name "Flying Dutchman" on its sails approached. Brook recounted the story of the Dutchman, how its captain, Vander Decken, went mad one day, throwing his crew overboard and cursing the gods, who struck down his ship in retaliation.
A voice called out from the ship, calling the giant Wadatsumi and ordering him to destroy the Sunny. Before the blow could land, though, the kraken reappeared and started beating up the would-be assailant, only stopping by the order of Luffy, who floated down from the water in one of the dive suits with Zoro and Sanji also squeezed in.
"Oh my god, he actually tamed it," breathed Itachi.
Before Decken could launch an attack, one of the volcanoes erupted, forcing all parties to make a run for it, with Wadatsumi carrying the Dutchman and the kraken (whom Luffy had apparently named Surume) carrying the Sunny. Before long, they fell into a trench, and falling boulders threatened to destroy the ship. Usopp used one of his new Pop Greens to create a wall of seaweed, halting the boulders, and the crew safely descended into the abyss, finally arriving at the ten thousand meter depth at which Fishman Island rested.
"That was close," said Robin. "I thought for a moment our coating would be destroyed, dooming us to be crushed to death by the water pressure down here."
Itachi had to stifle a chuckle at the sheer absurdity of her voicing that thought so casually. The others found it less amusing.
Immediately upon their arrival, though, they were surrounded by a host of giant sea animals being commanded by a fishman named Hammond. He offered an ultimatum: either the Straw Hats joined them, or they'd sink the Sunny on the spot.
Nami and Franky immediately started making plans to escape with one last Coup de Burst, but Itachi had other ideas.
"Hold on, there's no need to do something that risky, Nami. Do we still have one of those dive bubbles left?"
"Uh, yeah, but do you seriously want to go out there and fight them all?" asked Nami.
"Of course I do," confirmed Itachi. "Why risk running out of air when I can simply take them down?"
"But if you do, then they'll go straight for the ship!"
"You let me worry about that. I can handle them, trust me. I've got something new I'd like to try out."
Franky grabbed the dive bubble, and Itachi hopped inside it, rushing out of the Sunny just as Luffy was refusing the offer to join Hammond's crew. Once he was directly between the enemy and the ship, Itachi called forth his Susano'o, but it was unlike the previous times he'd done so. It went through the normal stages, from skeleton to skin to armor, and even grew legs. He'd managed to evolve it to the next stage during his training with Marco. The new Susano'o was even slightly larger than the sea beasts before him. Even so, bolstering the Sharingan by focusing his Observation Haki through them would prevent the use of the Susano'o from deteriorating his vision. Haki really was a wonderful thing.
Before Hammond and his crewmates even really knew what they were looking at, Itachi swung the Totsuka Blade, cleaving through all the giant creatures in one strike, killing them and their riders. Satisfied at the carnage he'd caused, Itachi deactivated the Susano'o and swam back to the deck of the ship.
"Well, that was almost disappointingly easy," he said, then noticed the rest of the crew were looking at him in utter shock.
"Whoa mama, and I thought I was cool!" exclaimed Franky. "But that was SUPERRRRRR cool!"
"So, your Susano'o has legs now," said Sanji. "That's pretty neat."
"Oh, man! That was the coolest thing I've ever seen!" said Luffy with stars in his eyes.
"That really took my breath away," said Brook. "Not that I have any lungs!"
"That was quite impressive. Wonder what other impressive secrets you're hiding?" said Robin, slightly more flirtatiously than she'd intended.
A few minutes later, they arrived at the giant bubble containing Fishman Island, where Itachi began directing them.
"I've been here before on trips with Whitebeard, so I can get you through the process of entering," he explained. "Sail around, the main entrance is on the other side of the bubble. We'll need to let the people at the front conduct a customs inspection, but I still have my ring from back in my Whitebeard days, so that should be more than enough to get us through without any problems."
"Why is that? Did the people here really like him or something?" asked Nami.
"You could say he's one of their greatest heroes. From what I'd heard from the rest of the crew, back when the Golden Age of Piracy began, Fishman island was constantly suffering pirate attacks and raids. Eventually, though, Whitebeard came along and officially claimed it as part of his territory, and that made the attacks stop, since doing so would invoke the anger of the World's Strongest Pirate. I wouldn't be surprised if some of the old crew came here to start new lives after the war two years ago. Any of Whitebeard's men are typically welcomed with open arms, though I heard recently that Big Mom had laid claim to it, so we'll see if that's changed."
"This is gonna be great!" exclaimed Luffy. "I can't wait to see Jinbe again!"
"Wait, Jinbe, the Warlord?" asked Usopp?
"Yeah, he's a good friend of mine. I probably wouldn't even be here without him."
"First Boa and now him?!" exclaimed Usopp. "You make the weirdest friends, Luffy."
"I suppose I'd consider him a friend now, too, considering how much of a help he was during the war. At any rate, we'll be reaching the front soon. Let me do the talking, okay?"
"Got it!" agreed Luffy. Everyone else just nodded.
Once they arrived at their intended destination, they breached the first layer of the bubble, which contained a bridge with flowing water that flows downhill into the second layer, with a large gate on the other side. As they crossed through the layers,a seahorse fishman motioned for them to stop. As he boarded, Itachi greeted him.
"Ah, I recognize you!" he said. "Mr. Spanna, right? How've you been?"
"Oh, Itachi! I didn't realize you'd be here! I've been great, thanks! How about you? I'd heard you left Whitebeard's crew awhile back and joined up with another, I guess these guys are it?"
"Yeah, I'm with the Straw Hats now. This is my captain, Luffy."
"Hello!" said Luffy excitedly.
"Straw Hat? Wow, you've gone from one powerful crew to another!" exclaimed Spanna. "Anyways, I gotta do my inspection. Normally I wouldn't bother with it since it's you, but ever since we came under Big Mom's rule, we gotta confiscate any candy we find on any ships. Sorry about that."
"Candy?" asked Itachi. "How come?"
"Big Mom requires us to send her a bunch of candy each month as tribute. If we don't pay, she'll send a bunch of her crew to collect, and probably ransack the island in the process. We even had to build a whole new candy factory just to meet demand."
"I'm sorry to hear that. On another note, what of Vander Decken? Is he still a nuisance to the princess?"
"Oh, you know it. The guy just won't quit, and we can never seem to track him down."
"Damn. We actually ran into the Flying Dutchman on the way here, but an undersea volcano erupted and forced us to run before I could take it out."
"Whoa, wait, you were planning on destroying that ship earlier?!" asked Nami.
"Yeah. For one, it was a threat to us, and for two, its captain, Vander Decken IX, has been harassing the Fishman Island's princess since before I ever even came here. He apparently has a Devil Fruit power that allows him to throw anything at a target he touches and it will always hit its mark. He uses it to constantly throw knives, axes, and anything else with an edge at her out of revenge for her refusal to marry him. As a result, she has to stay locked up in the palace."
"Wow, that's crazy," said Usopp. "I've heard of taking rejection badly, but that's on a whole new level."
"If we ever come across the Dutchman again, I'll be sure to take him down, Mr. Spanna," said Itachi. "You have my word."
"That's much appreciated, Itachi. The whole kingdom would be in your debt if you did that."
"Speaking of the princess, how are her brothers? Last time I was here they were still children. I bet they've grown quite a bit."
"Oh, yes! The princes have grown quite a bit since your last visit! But, funny you mention them now that you're with Straw Hat. I was recently informed that Prince Fukaboshi has a message he needs to pass on to your captain. He should be at Ryugu Palace, so once I'm finished with my inspection, you should head there."
"Thanks for the info. One last thing, and then I'll let you go about your business: Would you happen to know where we could find Cammie, Hatchan, and Pappagu? They're friends of ours."
"Can't say I recognize the first two names but Pappagu rings a bell. He lives up in Gyoverly Hills; if you ask around there I'm sure someone can point you in the right direction."
"Thank you so much, Mr. Spanna. I'll let you go on about your business now."
Spanna proceeded to scour the ship, and unfortunately for Chopper, he had to take his candy due to the rules laid out by Big Mom.
"Alright, everything seems to be in order! Once you all get past the gate, the port will be straight ahead; you can dock your ship at number four." Spanna hopped off the Sunny and pressed a button to open the gates, allowing them to sail through.
"So, Big Mom, what's her deal?" asked Luffy.
"She's one of the Yonko, like Whitebeard or your friend, Shanks," replied Itachi. "Though she's more on the ruthless side than either of them. If we keep pushing forward into the New World, we'll come into conflict with her eventually."
"Sounds exciting! If she's causing trouble for Camie and Jinbe's people then I'll kick her ass!"
"Somehow I knew you'd say something like that," lamented Nami.
As they docked and exited the Sunny, the people around them were bowing and kneeling. Not to them, but to the three princes of Ryugu Kingdom: Fukaboshi, Ryuboshi, and Manboshi had arrived to greet them. Fukaboshi's face lit up when he saw Itachi.
"My friend, it's good to see you again!" he exclaimed, rushing over and wrapping Itachi in a tight hug, which Itachi returned.
"Good to see you, too Prince Fukaboshi! You've grown so much since I last saw you! Come, I'd like you to meet my new crew." Itachi introduced each of the Straw Hats, saving the captain for last.
"Ah, the famous Straw Hat Luffy! We've been expecting you," said Fukaboshi. "Jinbe wanted me to pass a message along to you when you got here. He said 'Meet me in the Sea Forest, and whatever you do, don't fight Hody Jones."
"Hody Jones? Who's that?" asked Luffy.
"I can't say it's familiar to me. Sorry I can't be of more help," answered Fukaboshi.
"If someone like Jinbe has gone out of his way to warn us about him, perhaps he's someone who's up to no good," mused Itachi. "At any rate, if that's the case then we're sure to run into him at some point or another."
Meanwhile, Hody Jones and Vander Decken met in the Fishman District at the Noah, and formed an alliance in order to bring down Ryugu Kingdom, and began making their plans. Hody had received a report that Hammond and his men had been found dead outside of Fishman Island, and with this new alliance secured, he vowed revenge on their killer. When Hatchan showed up to try and talk them out of it, Decken marked him with his free hand and threw several volleys of arrows at him, forcing him to flee.