I remember that the One Piece underworld was shown in the Punk Hazard arc, but hardly anything was seen; in fact, I only remember that Stussy and Morgans are there; the rest are pure NPCs.
I'll change that here, since much of the "One Piece Arc" of this fic will be a relevant element, so I'll explore it as much as I can, adding and removing characters.
-----------------------------------------------------------------------------------------------
Third-person POV.
In a dimly lit area, a man wearing somewhat loose clothing can be seen next to a woman in a secretary's outfit, eating aimlessly.
Woman: "Steel productivity has increased considerably since the acquisition of the Alter Islands; that leads to an increase in the weapons available for manufacture and sale, sir."
???: "Fine, only the price of heavier weapons and spare parts will increase; basic weapons will remain the same. I'm also planning to increase the price of ammunition. What do you think?"
Woman: "I don't recommend it, sir, since the competition has lowered the price of these over the past few months."
???: "Oh, yes, remember to put that on the list of people I need to get rid of."
Woman: "Yes, sir."
???: "Follow them later; we've reached our destination."
Ahead was a door leading to a room; nothing special could be seen, except that it had a window from which nothing could be seen except that there was light inside.
The two entered without asking permission or anything, just walking until they reached a sofa, where the man sat down and the woman stood behind him with a diary to write down any events.
In front of him were three people, one sitting like him and two standing behind him like the woman.
One of the men had his face painted and somewhat odd features; the other looked hunched over, with a garment covering most of his body and snot hanging from his nose. The seated man had blond hair, a garment that looked like bird feathers, and glasses covering his eyes.
???: "I hope this meeting is worth something, Doflamingo, since I'm getting bored of wasting time."
Doflamingo: "You have nothing to worry about, since I have something that will be useful to you." At that moment, he took out some documents, which he passed to the man.
???: "Wow, where did you get this information, Mary Goise?" he said, glancing at the papers.
Doflamingo: "I have some high-ranking contacts who can give me some very important information."
???: "Exchange of favors? But what can you offer in exchange for this information?"
Doflamingo: "The important thing isn't what you know, but what I can do," he said, pushing his glasses up with a smirk. "I can be that bridge of information you might need, both from some pirates and high-ranking World Government agents. I just ask that you include me in the underworld circle."
???: "Generally, to enter the circle, you must be someone with a lot of influence in the underworld or other areas, but with this, perhaps I can make an exception."
Doflamingo: "I would be deeply grateful." After all, this was the first step toward taking over the underworld.
???: "I just want to ask how true it is that the Ope Ope no Mi can grant immortality."
Doflamingo: "You'll just have to trust me for now."
The man snapped at the shamelessness of the guy in front of him.
???: "No matter, I'll find out sooner or later, whether from you or someone else."
Doflamingo: "I look forward to seeing that; I also have another topic to discuss, which is that group of so-called heroes who have been ruining my business."
???: "The loss of auction merchandise is a great sadness; how fortunate it doesn't affect my own business at all."
Doflamingo: "Then it won't do anything to them; I can give them something else, maybe men or a few resources to eliminate them for good."
???: "I don't remember saying that, do I, Selina?"
Selina: "You didn't say it, sir," said the woman behind the man.
???: "Did I say it, Dofi?" she asked the Doflamingo.
Doflamingo: "N-no, he didn't say it," he said a little nervously.
???: "Then don't put words I never said in my mouth, or I don't know that you want to have any trouble with me, is that clear?"
Doflamingo: "Yes," he said a little slowly.
???: "DID I SAY IF THAT WAS CLEAR?!"
Doflamingo: "Yes, it was clear," he said a little louder and more resigned.
The man didn't say anything at all in response to Doflamingo's attitude, as he was used to people like that.
???: "I've already sent my men to do something against them."
Doflamingo: "May I know who sent them?"
???: "It was Artic and Marie."
Doflamingo didn't like that very much; you could tell by the expression on his face.
Doflamingo: "I would have sent more qualified people to ensure the objective is achieved."
???: "The rest are busy. Only Balesca was available, and I'm not going to send her if I'm not at my base protected. She'll be with me, acting as my bodyguard."
Doflamingo: "And—?" He couldn't finish his words as a woman's voice was heard.
Balesca: "I'm here," said the woman standing between Diamante and Clover, frightening the three with her sudden appearance.
Doflamingo: "How...?"
???: "That doesn't matter. The important thing is that if they fail to accomplish their mission, I'll go after them myself, so stop crying and complaining about your losses that only affect you."
As he stood up to leave with the two women, Doflamingo asked him one last question.
Doflamingo: "Why do you always keep your best asset by your side instead of sending her to do something, knowing the high probability of success?"
???: "Is she trying to get information out of me? Well, it doesn't really matter to tell her." He turned to look at Doflamingo: "I may be strong, but I don't think I'm invincible. With all the enemies I have, I can't be so complacent and be such an easy target. I'm not like you; I'm better than you, and you can't change that, Exile." After saying that, he left without looking back, leaving Doflamingo and his henchmen alone.
Balesca: "It's fine to say all that, my lord. He'll most likely retaliate."
???: "Don't make a fool of a clown like him; just ignore him." She nodded and followed the man.
Selina: "Sir, before I forget, I have information about this new group that's targeting the Navy and the World Government."
???: "Remind me what it's called," she said, wiping the hatred away with her finger.
Selina: "They call themselves the Revolutionaries, and they're commanded by former Vice Admiral Dragon."
???: "Dragon, what good memories. Perhaps I can make a deal with him. Since he's not a Marine and wants to fight with the world, it might be something good for us."
Selina: "Do you really think so, sir?"
The man remained thoughtful as they continued walking.
???: "Well, only time will tell." Only to keep walking, disappearing into the darkness.
*In the room*
Clover: "What are we going to do, Doffy?"
Doflamingo: "Let me think," he said curtly, calming himself for a moment and returning to his senses. "I'm sending those losers to their deaths. Chances are they won't be able to kill them, so they'll want information about their attackers." He stopped to look at his most trusted subordinates. "Give half of the relevant information to G2 and the rest to G3, and don't let them discover you."
Both: "Understood."
Doflamingo: "This will speed up my plans, although I'm not ready to take that guy's position. If only one of us is destroyed, that's more than enough for me." He said, laughing on the spot.
*Elsewhere in Paradise*
It's been days since the group of heroes left Loguetown, and they're now in Paradise; more specifically, they're halfway to Sabaody.
Right now, they're in the middle of the night, with a heavy rain barely making it possible to hear anything happening on the ship.
And on that same ship, in the middle of it all, there was a person chained and crucified on a cross; that person was Dante, who hadn't been able to free himself since the journey began.
While he was there, the others were drinking coffee and talking about the current situation they were facing.
What they didn't know was that a small ship was behind them, tracking them down.
Isis: "Are you sure we can handle this?"
Arthur: "Maybe if we take him on one-on-one."
In the middle of them were three bounty posters, which they were analyzing. These were provided by Morgans, since Dante had asked about them before searching for Shiki.
The first bounty poster: Arctic, the deranged, reward of 234,900 belly, dead or alive. In the photo, you can see the guy with the hammer Arthur fought with.
The second poster: Marie, the Ephemeral Spark, bounty of 290,000,000 Belly, dead or alive. In the photo, you can see Marie attacking someone with her hand extended.
The last poster: Hogan, the martial artist, bounty of 650,000,000 Belly, dead or alive. In the photo, you can see his raised fist, where something no one knows what it is is concentrated.
Arthur: "If we don't find them like the first time, maybe not."
Sulli: "We'll have to come up with a plan to defeat them effectively and quickly. What do you say?" she says, turning around and looking back, Arthur and Isis following her gaze.
Trini was sitting a little isolated; she was playing with the balls of her pistols, her eyes closed, concentrating, as if she felt something.
Trini: "I have a feeling something's going to happen now."
Sulli: "What do you think will happen?"
She didn't answer. She looked at Arthur.
Trini: "Go with him just in case."
Arthur: "It's a pain, but I'll come." He stood up and walked slowly and reluctantly away.
Trini: "Let's pay attention to what happens."
*Elsewhere on the ship*
A crucified man is seen; on the outside, he looks alive, but on the inside, he's dead.
The rain covers his shame, and his dignity is stripped away like the drops falling on his body. Without strength or desire to do anything, he just waits for time to pass so he can be free and cry in a corner without anyone seeing him.
The rain muffled every sound, enough so that he couldn't hear anyone's footsteps on the ship, at least not those coming from outside.
Dante, in his catatonic state, having barely moved a muscle in the days, saw someone in front of him. He had a waterproof hood that covered almost his entire body; considering it was nighttime, nothing could be distinguished about this man, only the object he was holding, which was a hammer.
Dante: "I didn't know a carpenter needed such a big hammer. Tell me, is it compensating?"
???: "It compensates the same as your giant sword."
Dante: "It's made to kill large beasts; anything small wouldn't do. Do you work with giant nails?"
???: "No, I work killing people." At that moment, he positioned the hammer at a horizontal angle, pressed it, and rockets shot out of one of its faces, propelling and increasing both the speed and force of the hammer.
The hammer's movement was designed to target Dante's position. Being tied up and with his muscles somewhat atrophied, he couldn't defend himself, so the attack hit him square in the stomach.
The blow destroyed the cross Dante was on, sending him flying near the ship's cabin.
Dante vomited the remains of his lunch, throwing it to the ground and moving his body to the side so it wouldn't fall on his face or clothes.
Without waiting any longer, the man leaped with Haki coated on his hammer, activated Boost, and with a vertical swing launched himself straight at Dante's head, only to be intercepted by a spear in midair.
Arthur: "My, my, who knew I could have a rematch with you, Artic?"
Artic: "Think fast," he said as he got up from the ground.
Arthur didn't understand what he said until he felt someone behind him. He turned around only to find a hand and feel a heat on his face.
The spot where Arthur was standing exploded, moving him about 3 meters from his position. There was a woman with her hand outstretched.
Marie: "I would have made the explosion stronger," she said, scolding herself.
Arthur looked over to where Dante was. To his horror, Artic was already there, about to try to crush his head a second time.
The moment the hammer fell, Dante miraculously, using only one arm, coated his skull with Haki, negating much of the damage, but not all.
The blow shattered the casing, sending Dante tumbling to the floor below.
Dante: "It's a good thing I never stopped moving one arm." He still couldn't move the rest of his body; he just needed time, which he didn't know if he had enough of. He was still chained, but only on one leg and the other arm. He could use Haki, but the sea stone was too strong; even with Haki, he couldn't break it. For that reason, he couldn't block the first attack with his arms, but he did use Haki.
The stone weakens Devil Fruit users, and Dante isn't one.
Upstairs, Arthur was left alone with the two assassins. He positioned himself defensively, at a distance where he could see both of them at the same time.
Artic: "Let's finish quickly before their companions arrive." Marie simply nodded.
They both launched themselves at him, only to be stopped by the long spear.
Arthur has spent almost four years studying the art of the spear; by now, the spear is part of his body, like another limb. He knows the attack range, the spin speed, and everything about the use of Durindana.
With extreme ease, he twirled his spear twice, once to scare Artic and the other to ward off Marie.
They both tried to attack at the same time, but Arthur was able to block both attacks at the same time.
Artic: 'We can't keep going like this,' he thought. He looked at his companion at his side, who stared back.
Artic advanced while Marie stayed back. Arthur frowned.
The hammer tried to land blows, but they were blocked consecutively until Artic pressed a button and the hammer turbocharged at full speed toward him.
Arthur used the entire spear to block the attack, leaving him open for a blow. He managed to protect himself, but Marie appeared on the other side, with a Haki-powered punch directly next to the rib where the heart is.
He'd used both hands to hold the spear and withstand the hammer blow, so he didn't have time to move it and try to strike back. All he could do was drop his spear and hope to dodge the attack, but that would leave him without his weapon and no way to attack or protect himself.
Just then, a shot rang out. Marie stopped dead in her tracks, clutching her shoulder, where it was starting to bleed.
Trini: "I can't believe they ignored me," she said, pointing at Marie.
Isis: "And me," she said as she sent a wave of air toward the three of them, sending them flying.
Dante: "And me." Dante's voice was heard in the hole, but everyone ironically ignored him.
The three landed on their feet, as the wind was meant to dislodge them; he wasn't going to use much force with Arthur in the attack area.
Arthur placed his feet on the wall and launched himself at Arctic, performing a vertical slash with Durindana. Arctic protected himself but was sent flying back to where he was.
Marie was about to act, but Isis was already upon her, and with a flick of her hand, she knocked Marie down, breaking the deck and falling to the second floor. Isis then went after her, leaving Arctic alone against Trini and Arthur.
Down on the second floor, Marie was getting up from the floor with her hand on her bloody shoulder; shortly after, some marines appeared with guns pointed at her.
Marine: "Surrender, and face justice for attacking a naval vessel."
She paid no attention to them; with her hand, she threw a little blood at the men so that when it hit, it would explode.
Isis arrived at that moment and, in a move no one knows why, tried to hit her with a blow covered in air. Marie easily dodged it, delivering an explosive blow that sent Isis tumbling down a corridor.
Marie: "Fool," she said, propelling herself with an explosion toward Isis.
Up above, Artic wasn't having a great time; he could barely block Arthur's attacks while also trying to block Trini's bullets. They weren't lethal, but if they kept piling up, he'd faint from bleeding out. Furthermore, whenever he went for her, the other would intercept him, preventing him from continuing.
He was skilled in combat, but Arthur could stop him with a weapon; she couldn't land a blow, but neither could he. It was a stalemate. The only difference was Trini's presence.
He had no choice but to create the retaining walls to protect himself from Trini.
With speed, he entered the room on the ship's deck and destroyed it, creating walls in places where he could hide. This seemed annoying to Trino, since he already had places to hide.
Trini: "It seems the rat wants to hide now, pathetic."
The ship, with each passing second, was in worse condition. Above, it was being destroyed, while inside, it was being bombed.
Marine: "Headquarters, we've been attacked by assassins from the underworld. We're in "the—"Aaahh," he couldn't finish speaking as a sudden explosion hit him.
Inside, the marines could be seen flying from every explosion.
Isis was moving toward the ship's kitchen, while Marie followed her.
Marie: "Don't run away; fight like a man."
Isis: "That doesn't make sense."
Marie grabbed a piece of debris and threw it. Isis reached out to throw it back but noticed the rock had blood on it, and at that instant, it exploded. She couldn't defend herself, so the explosion hit her, sending her sprawling into the kitchen.
(Note: I just read what I wrote, and it's quite funny and ironic.)
Isis tried to get up, but she was injured, so it was difficult. As she continued, she realized she was staring at Marie.
Marie: "Let's see if you survive this."
She reached out as if grabbing a ball, only for explosive energy to gather in her palm. What she was doing was creating an explosion and concentrating it, then doing another explosion in the same place, gathering all the energy in one place.
Isis looked at this in fear; not only could it kill her, but it could destroy the entire ship.
Just as she was about to speak, someone behind her injected her neck with a syringe.
Sulli: "You lost your focus." He'd been waiting in the kitchen, hiding this whole time, since the plan from the beginning was to lure Marie here.
Luckily, the ball didn't explode but disappeared. The energy was released passively and slowly, so it didn't cause any damage.
Sulli punched Marie hard in the rib, causing her to kneel.
Marie: "Sexist," she rebuked him.
Sulli: "Gender equality, bitch," she replied.
Marie: "Tell me what you injected me with."
Sulli: "Poison with a little bit of sea stone."
Marie: "What?"
The sea stone was obtained from the chains that kept Dante tied up. With Arthur's help, he managed to scrape a little stone off that chain—not much, but enough to make this type of poison.
Isis decided not to waste any more time and, with the wind in her fist, punched Marie. Marie followed her until they were perpendicular to the kitchen's emergency exit door. With her hand, she sent Marie flying with all her might, breaking the door latch and sending Marie flying off the boat and into the sea.
Sulli: "Will she be okay?" he asked Isis, who just shrugged, signaling she had no idea. "So why did you do that?"
Isis: "If I told you I was already bored, would you believe me?"
They both remained silent, not knowing what to say.
Dante: "I thought the boat would fall apart and we'd all die."
At that moment, Dante appeared, crawling across the floor like a worm with only one hand. The room fell silent again.
Upstairs, the battle was still going on; Arctic was almost covered in blood. No matter how much cover he tried to gain, it didn't stop Trini's bullets from hitting him. With Arthur's help, he managed to shoot him, dragging him from where he was.
Artic was already tired and felt like he would soon faint. He was going to end up lost and captured by these people; he wouldn't allow that. Even if it cost him his life, he would take one with him.
Arthur, seeing this, seized the opportunity; he tried to plunge the spear into Trini's stomach, thinking he would dodge it, but he didn't. The spear was embedded, and Arthur was taken aback, and Artic took advantage of it to strike him, sending him far away.
Arthur flew away with his spear, shattering the stomach, intestines, and other nearby body parts with the violent force of the spear thrusting from that spot.
The man, ignoring the immense pain he was in, went straight to Trini's to end this.
He jumped and, with the turbo boost from the hammer, went to her, aiming the hammer for a vertical blow to her head.
Trini fired three shots at him in the chest, which he ignored as if they had never hit him, only for the bullets to run out.
When he was about two meters away, Trini tried to cover herself with her pistols; out of nowhere, a long blade pierced his chest and missed.
Artic fell a few meters to the ground, his stomach open, bleeding from his mouth, multiple wounds in different parts of his body, and a spear piercing his chest; he couldn't take it anymore.
The man fell dead.
Trini looked from Artic to Arthur, only to see him in the position as if he had thrown something.
Arthur: "The way I was, I'd probably die no matter what happened."
She lay on the ground to rest; for a moment, she was scared that the hammer would hit her.
Trini: "I just wanted to thank you; you don't need an excuse to do what you did."
They were both on the ground, thinking about everything that had happened. No one noticed the ship in the distance; it was barely visible, but if you didn't focus your gaze on the specific spot, you wouldn't see it.
Hitman 1: "They missed. Artic was impaled, and I think I saw Marie fall into the sea, so she was lost," said the man with binoculars looking at the marine ship.
Hitman 2: "Let's go. We have nothing to do here; let's tell the boss what happened as soon as possible."
And just like that, the ship disappeared without anyone noticing. There will be questions about how Artic and Marie got to the marine ship, but there will be no proof of anything.
-----------------------------------------------------------------------------------------------
E.S.: For every Power Stone you give to this fic, you will be saving a baby kitten.