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It all started with a fogbank.
Normally, Ace would not be too worried about fog. He was a Commander in the Whitebeard Pirates, normal weather just didn’t scare him anymore. Striker could handle most storms easily enough, even as small as it was.
This wasn’t a normal fogbank though. This was New World fog. New World fog was never a good thing. Ever.
Of course, Ace tried to go around. He wasn’t an idiot. However, the fog seemed to have other ideas, given that it moved to block his path. Then it started moving towards him.
Which was how Ace had ended up driving Striker as fast as he could away from the predatory weather phenomenon. Unfortunately, it was gaining. So, there was only one thing to do.
He had to fight it. Steering Striker into a quick U-turn, he concentrated his fire on his signature technique. As he and the fog flew at each other at high speeds, he drew his now-flaming fist back and let out a challenging cry.
“FIRE FIST!”
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Fog in Tokyo Bay was rarely cause for alarm.
However, this fogbank had appeared in the span of a single second, which made it odd. Which meant it was probably the product of a quirk. A previously unknown quirk, given that it had been verified that the only villain capable of weather manipulation on this scale was still in jail. Thus, Tokyo’s hero community was on edge.
This included the current Number 1 hero, Endeavor, which meant that Shotou had been dragged along too. Ever since Shotou had gotten his provisional hero license, Endeavor had been taking his son with him to most of his fights, since in his words “even if I’m number one now I’ve spent too much time on you to have you not take my seat”.
At least Midoriya was there too. His ever-inquisitive classmate had wanted to know about whatever new quirk was causing this. Given that Endeavor was focusing all his attention on the fog, Shotou was free to speak with Midoriya as much as he wished. Or, rather, listen to Midoriya mumble his theories and analysis.
“If it is an attack, most likely a teleportation quirk. Maybe moving through fog allows for instant transportation? Could be a newly awakened quirk that allows for massive fog generation, and thus an uncontrolled manifestation. What are the dimensions of the fog? What is its composition?”
All hypothesizing was put on hold, however, as a huge gout of flame burst from the fogbank.
There was a small black dot emerging from the hole in the fog as the flames died down. Midoriya immediately pulled binoculars from one of his pouches. Shotou focused on his analysis-- if this was a villain, Midoriya’s advice would be critical.
“One male on a single-seat motorized boat. Manifesting flames around his feet, likely powering boat. No armor, developed muscles. Unlikely to be the one who generated fog cloud. I think he’s confused. He’s looking around like he--”
Midoriya stopped.
“What’s wrong?” Shotou asked.
“I… there’s a skull and crossbones tattooed on his back. I think he’s a pirate.”
“Wait, a pirate!?”
Midoriya and Shotou started, looking at the source of the voice-- a civilian who had apparently been listening in on Midoriya’s analysis. His exclamation was taken up throughout the crowd.
“A pirate?”
“Is he coming to raid us?”
“He must be really powerful if he thinks he can raid Tokyo alone!”
“It’s probably just some villain who thought a pirate theme would be cool.”
“Everyone knows ninjas are better, just look at Edge Shot!”
However, at the front of the crowd, Endeavor grinned a vicious grin.
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Ace was, to put it mildly, confused. He had sailed into the fog cloud, burning away a huge swath of it with his flames, and emerged on the other side. In front of an island he was sure hadn’t been on the other side of the fog cloud before. The structures on the island were titans that shined in the sunlight-- they looked like they were made of glass and metal. On the shore he could see a crowd of people. He could also feel a source of hostility on the shore ahead, and could feel something building.
A blast of flame rocketed into the sky, easily matching the usual result of an uncontrolled fire fist like the one he had just used.
“PIRATE! YOU ARE NOT WELCOME HERE!” Shouted a deep, powerful voice from the shore. It kind of sounded like it was being directed through a Den-Den Mushi. “COME CLOSER AND YOU WILL FACE THE HERO ENDEAVOR!”.
Well, that was clearly a challenge. And while it would not be accurate to say a Whitebeard Pirate never backs down from a challenge (most of the crew wouldn’t play Ace in poker anymore, no matter how much he goaded them), Ace very rarely let a challenge as arrogant as this one slide.
Plus, he kind of wanted to punch something.
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“He’s coming closer.” Izuku related. It wasn’t really necessary-- Shotou could see him now. His ship was obviously rather fast.
His father had probably wanted this. His latest obsession was trying to “really earn” the title of Number 1 Hero-- he was trying to get his approval rate higher than All Might’s had ever been. Big, visible fights featuring Endeavor had become regular features on the news.
Completely unrelated to this, Shotou had been watching a lot less of the news recently. He would probably leave at this point, but Izuku was muttering to himself in that way that happened when he got really into his analysis. Someone had to stick around to make sure he didn’t get burned to a crisp by collateral fire blasts.
Endeavor tossed the megaphone he had been holding to the side, where a sidekick scrambled to catch it. He cracked his knuckles. “I WARNED YOU!” He boomed, extending his hands forward and letting loose with a massive blast of flame, even bigger than the one he had used when showing off before.
What a shame. Izuku had seemed so excited to learn about a new villain. He was about to turn around and pull his friend with him when he saw a figure standing in the smoke.
No way. The villain was standing there, totally unmarred. Even his boat was untouched. He was just standing there, arms crossed, looking rather bored.
Maybe Shotou would stick around for awhile. Just to see what happened.
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“So, are you blind, or are you just one of those people who doesn’t touch bounty posters?”
Ace felt vaguely insulted. No one had actually tried to use fire against him since he had become a commander. His devil fruit was common knowledge. Maybe this guy thought he had the only fire-type Devil Fruit? That was just willfully ignorant-- Ace was pretty damn famous, after all.
“Hmm. So you can withstand my flames, criminal. But I am not done yet.” The man (who, Ace had to admit, had pretty good taste in facial hair) breathed in, and exhaled, letting loose with a concentrated beam of pure flame, much hotter and faster than the last attack.
Ace just let it wash over him like a warm breeze. “Seriously, it’s not going to work. You don’t recognize me at all? Fire Fist Ace, of the Whitebeard Pirates?”
“Who you are matters not to me. No one can match my flames, even as they try to resist my weaker attacks. Take this!”
The fire was blue this time. Admittedly, these looked hotter than most of the attacks Ace could pull off. They might actually damage Striker. So, instead of just letting the fire pass him by, Ace seized hold of the fire and condensed it into a ball, which he held in one hand.
“Okay, big guy. You can certainly dish it out. Let’s see if you can take it!”
Ace threw the fireball, twisting it as he did so into a cone shape. It flew at his opponent (apparently named Endeavor? Ace couldn’t judge, he’d heard worse) and impacted him, creating an explosion of blue flame. No one else had been in the radius-- the crowd of spectators had quite wisely backed up at this point.
When the smoke cleared, Endeavor was standing, arms folded, clearly ripping Ace off entirely. “You think I can be harmed by my own flames? There is only one true master of fire here, and--”
He was cut off as Ace rocketed towards him and buried a knee in his gut.
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This was the best villain fight Shotou had seen in ages. The pirate villain (Ace?) had engaged Endeavor in hand-to-hand combat, and was clearly winning. Not helped by the fact that every time Endeavor landed a hit on Ace, Ace turned the part of his body that was hit into flames and reformed, no worse for the wear. Despite his comparatively tiny size, his blows resonated with strength, and Endeavor was doubtless going to have plenty of bruises and broken bones when this was over.
Shotou had relocated Izuku further back, and they were safely behind a barrier of water created by Backdraft, along with most of the spectators. Izuku was scribbling frantically in his notebook, but Shotou couldn’t help but notice that he was looking worried.
“Midoriya.” A gruff, familiar voice came from behind the two.
Aizawa wasn’t in “costume” at the moment, instead wearing sweatpants and a wrinkled T-shirt but his goggles were around his neck and he had his Capture Scarf clutched in one hand. Despite his disheveled appearance, he looked like he was all business.
“Y-yes sir?” Midoriya stammered.
“I want your opinion. Do you think Endeavor can win this fight?”
In Shotou’s opinion, Aizawa sounded like he had his own opinions on the subject. Midoriya still answered, his voice low. “No. Not really. His fire is having zero affect, and his physical attacks are similarly useless. I don’t know when, but he’s going down. However…”
Aizawa quirked an eyebrow. “Yes?”
“I’ve noticed something. This Villain-- Ace-- isn’t just letting every physical attack pass through him. The flame-charged punches and kicks Endeavor is using-- the ones he uses to melt stone for vertical maneuverability in the city-- he’s dodging all of those. It’s possible that he has a threshold of heat that he can withstand.”
“And what are Endeavor’s chances of landing one of those?” Aizawa continued as Shotou marveled at Izuku’s analytical abilities. He hadn’t noticed that at all, but now that he was looking closer Ace was dodging every one of those attacks-- with ease, certainly, but he was dodging them.
“Almost nonexistent without help. I don’t know what kind of quirk Ace has, but I think it might include mild precognition? He starts to dodge those attacks before they’re even really happening. At this rate I think that Endeavor will go down before he can land a damaging attack.” Izuku replied.
“Then we’ll need to help him.” Aizawa slipped his goggles on and began to don his scarf.
Both students looked up at their teacher in surprise. “Not you two.” he clarified. “This is too dangerous for students. I want you two to work on crowd control so I can bring Backdraft into this. His abilities may be necessary.”
The two looked at each other, nodded, and moved. Izuku leapt with insane speed to Backdraft’s side and whispered something in his ear. Shotou, meanwhile, went up to the water barricade and placed his right hand on it. Backdraft created water rails that extended to the ground and then joined the two halves of the fence together, only separating from the structure when Shotou’s ice was nearly to him. Then, he went to Aizawa’s side, along with a few of Endeavor’s sidekicks and some other heroes who had arrived on the scene.
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Ace wasn’t even breaking a sweat. His opponent had stopped with the dramatic speeches after about two minutes into their fight, and was now just trying to defend himself. Not that he was succeeding. Ace delivered an uppercut to his chin and danced away, grinning.
“What’s the matter, big guy? You were all talk earlier, and you haven’t even hurt me once.”
Endeavor tried to catch his breath.
Ace decided to push further. “Man, you are pitiful. Tell you what. I’ll give you one good shot against me. Give it all you’ve got.”
Not that it would work. Ace wouldn't even have to dodge, unless it was one of those lava punches his opponent had been throwing out.
Endeavor straightened up and snarled at Ace. “I’ll make you regret that, Pirate.” Flames burst from the back of his arm and he flew at high speeds towards Ace, fist streaking towards him at insane speeds.
But not heated up. He’d be…
Ace’s Observation Haki flared up. Danger. Extreme Danger. Get out of the way. Ace, on instinct, tried to shift into flame, but it felt like there was a blanket of hostile Armament Haki around his form. He could only roll with the punch when it came, slamming him violently up against a wall some 20 feet back.
He got up, form aching, to see the victorious grin on Endeavor’s face. “So you couldn’t react fast enough to avoid my strike, could you? Your arrogance has cost you-- I know your weakness now!” he gloated.
Ace groaned in pain. For all his faults, this guy could actually throw a damn good punch. He slowly got up, responding as he did so.“No, you idiot, it’s an automatic defense.” With the absence of his devil fruit powers, Ace was focusing his Haki. It was his only defence now. “Your friend over there used his power to disable it.” he said as he motioned to the shabby-looking man wearing odd eye-concealing goggles just outside the crowd.
Endeavor’s eye twitched, but he gave an only slightly murderous smile to the other man. “Eraserhead! Thank you for your assistance, but please stay back! Even without his powers he is still a formidable threat-- though I am certain I can take him now.”
Ace snorted. “You move like a geriatric gorilla old man. I can still kick your ass, with or without my devil fruit.”
“But can you fight all of us?” Ace felt an attack coming from above. He dodged to the side effortlessly as another man in spandex crashed to the concrete where he had once stood. Now, in the lull in the action, Ace could see other costumed characters surrounding him. Slightly more alarmingly was the wall of water that was surrounding him and the rest of the combatants.
Ace looked around, judging his odds. “Yeah, I think so.” He grinned as his skin began to change colors, a black sheen taking over his normally pale skin.
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Izuku’s eyes widened. Shotou’s were doing the same. This was impossible-- no one could still use their quirk while Eraserhead was suppressing it, aside from mutation quirks, which Ace clearly wasn’t. And yet, here he was, covered in a black shine that seemed to let him shrug off any attack that came at him, and if anything he was even stronger than before.
“That’s not possible” Izuku breathes. He doesn’t have his notebook out. He’s just watching with growing horror as one man dismantles a crowd of pro heroes. They barely even notice as a familiar face comes running through the crowd. Not weaving his way through things-- literally through it.
Mirio stops by his fellow U.A. students. “What’s going on-- oh, my!”
The scene is carnage. They can’t keep Ace down. He dodges strikes with ease and tanks anything that does hit him with little effort. Eraserhead can’t even keep an eye on him all the time, and when he loses sight due to the crowd or having to blink, flames take out another group of heroes.
“I need to--” Mirio starts, but Izuku holds out his arm. “No!” he shouts.
Mirio looks confused. “They need my help, Midoriya. I can phase past his blows and fight back better than anyone in that melee--”
“No, you can’t. Mirio, I just saw him punch Untouchable. That shouldn’t be possible-- his personal force field repels all physical attacks moving at a speed faster than 1 meter per second. I think he can nullify the defensive qualities of quirks somehow.”
Shotou and Mirio both gape at Izuku. “How could he do that?” Shotou asks.
“I have no idea. My only hypothesis is that he can change his body to match quirks that are used against him, but even that doesn’t explain everything. There are too many unknowns here. We need to make a plan, we can’t just rush in. Wait and watch, and an opportunity will--”
He didn’t get any further before he was interrupted by a shout from Ace that drowned out all the noise of conflict. “ENOUGH!”
A wave of pressure swept over the three. It was like Stain all over again to Shotou, and he found himself paralyzed by the sheer force of Ace’s will.
The rest of the crowd and many of the heroes weren’t so lucky. Their eyes turned white and many collapsed, foaming at the mouth. Those that weren’t near the epicenter swayed and collapsed to their knees as if under an incredible weight.
Shotou watched as Ace lifted a single glowing hand towards a swaying Eraserhead. Then there was a familiar shout from his side.
“NO!” cried Izuku, as he somehow broke free of his paralysis and dashed towards Ace. He didn’t bother making contact with the pirate, instead kicking early and creating a huge gust of wind that broke Ace into flames which quickly reformed.
“Damn, you people are persistent. Most people can’t take Conqueror’s Ambition and keep standing like that.”
Izuku said nothing, but clenched his fists. Shotou wanted so much to go to him, to be by his side.
Then he was sprinting over, his limbs suddenly free. Mirio was with him, and soon both were flanking Izuku. They stared down the pirate.
“We’re not going to let you hurt anyone else.” Izuku finally said.
“Look, kids, I don’t want to hurt you. I really only wanted to finish things with fireface over there.” He said, indicating Endeavor, who was conscious, if only barely. “But that guy intervened, which means he’s fair game. Same with anyone else who tries anything.”
If the barely veiled threat phased the the other two, they didn’t show it. Shotou was now realizing that this guy wasn’t like Stain-- he was dangerous, certainly, but there wasn’t any bloodlust in him. He didn’t want to kill them. Even so, they couldn’t just stand by and let Eraserhead get hurt.
“Right then. I’ll just take it easy on you--” Ace started. That was as far as he got before Shotou let loose with a wave of ice. Not quite as big as some of the ones he had fired off during the Sports Festival, but it was impressive. It was met with a wave of fire. Izuku dashed off to the side. Mirio didn’t bother-- he ran right through the rushing ice.
Judging by Ace’s confused “Wha-” before the flames cut out, Mirio’s trick worked. Shotou jumped atop the glacier he had just created and dashed towards the action, his footing sure on the ice as it always was.
Izuku and Mirio were double-teaming Ace, and it was working out fairly well. Mirio’s quirk meant that he and Izuku wouldn’t trip over each other, and Izuku could let loose with blasts of wind to constantly disperse Ace before he could work up any big attacks.
Unfortunately, this couldn’t last. As Shotou watched, Ace’s fist turned black and impacted Mirio when he was phasing, knocking him backwards. Shotou shouted out a warning and Izuku jumped back as a much more controlled blast of Ice flew towards Ace, but he met it with a similarly condensed flame and melted it easily.
“You’re pretty good with that ice of yours, kid, but it won’t give you the advantage, and I’ve got way more experience than you. Best give up now.” Ace stated calmly. He was still infuriatingly unruffled-- though Shotou could see some bruising forming on the pirate’s chest, presumably from Endeavor’s earlier strike.
Shotou saw Izuku come in from behind, bouncing off a nearby wall. Ace leaned to the side, dodging without even looking, and grabbed Izuku, redirecting him into Shotou’s artificial iceberg. The ice cracked.
“And you’re just full of surprises, aren’t you kid. But neither of you can hurt me. You clearly don’t have Armament Ambition and I don’t see any Seastone on you.”
He was right. Shotou couldn’t see any way to hurt him. Unless… he had been working on something. A theory. Maybe he could use it here. It would take some work-- some improvising, but it might just finish this.
“Deku. Can you buy me some time? I have an idea.” Izuku had pulled himself out of the iceberg during Ace’s speech. He looked concerned, but nodded.
“You know I’m just going to focus on you now, right?” Ace directed to Shotou. “Your friend can’t stop me, not by himself.”
As if to prove him wrong, Izuku dashed at the villain. Ace seemed unconcerned, but as Izuku approached his eyes widened. He tried to jump away, but Izuku’s leg still clipped him.
It sent him rolling away for a few meters before he managed to right himself.
“He’s not alone” said Eraserhead, now recovered from the psychic pulse. Shotou couldn’t see them, but clearly his eyes were firmly fixed on Ace. “Todoroki, get to work on that plan of yours. I don’t know how long we have.”
Then he dove into combat. Mirio was soon there as well, recovered from Ace’s earlier attack, and a few other sidekicks and heroes who were still combat-capable jumped in. Shotou couldn’t keep track, really. He was focusing. His left hand was pressed to the glacier, and Shotou was trying as hard as he could to control the heat it was putting out. If his attack went off before it was ready, it would all be ruined.
The fight was heating up. Eraserhead, now that he knew his target’s capabilities, was playing keep-away, and the smaller crowd meant that he could keep his eyes on him at all times. There were occasional bursts of fire, but Izuku was blasting those away with his high-power kicks. Ace seemed to have forgotten about Shotou. It looked like he was getting flustered.
Shotou had to fight the urge to jump as Mirio popped up next to him, displacing himself out of the ground like he often did. “So, Todoroki, what is the plan? I don’t think we can hold him for much longer.”
Shotou spoke, his voice wavering as he tried to maintain focus. “You’ll see. In one minute, I want you to get Midoriya to hit the ice where he impacted it earlier. I should be ready by then.”
Mirio looked confused, but jumped and dropped below the ice, reappearing on the battlefield moments later.
A minute later, Shotou was indeed ready. Midoriya launched himself at the ice with a cry of “Smash!”
Then the water that had been painstakingly melted by Shotou, made all the more difficult by the need to not melt the ice walls, washed out, pouring out to meet the crowd of heroes. More importantly, washing over Ace.
It worked surprisingly well. He went limp, and when the water washed away into the bay, he was barely standing.
Barely being the key word.
“I’m… not… done… yet” Ace panted.
“Oh, come on!” Came a cry from the small group of heroes, who were similarly exhausted, though they had all fared better in the miniature flood.
“What is this guy made of?” Came another.
“Fire, I think. Or maybe metal.” answered a third.
“What is it that you want?”
Everyone turned to face the last speaker. It was Izuku.
“W--What?” Asked Ace.
“Kid, we can’t just give villains what they want! We have him on the ropes, don’t give up yet!” shouted one of the heroes.
“I-I’m not sure he is a villain. This doesn’t add up.” Izuku replied. He directed his gaze back to Ace. “What did you come here for?”
“I didn’t even want to come here!” Ace shouted. He appeared to be gathering strength again, and the heroes immediately went on alert. Several pointed hands or weapons at him. Nevertheless, he continued. “I was sailing along when this fog cloud started chasing me. I tried to disperse it with some fire, but it clearly didn’t work, and now I’m here. I don’t even know where here is.”
Izuku was paying close attention. There was silence for a moment.
“Uhh… kid?” A hero near the edge butted in.
“Hold on, I think he’s muttering something.” One who was closer to Izuku said. He leaned in and listened for a moment before his eyes went as wide as dinner plates.
Literally. Shotou was pretty sure this guy was a shapeshifter.
“What do you mean alternate dimension?” He shouted.
Everything went silent as every single person who was still awake stared at the green-haired and suddenly very anxious hero-in-training.
Shotou’s first thought was What.
His second thought was Actually, that would explain a lot.
After that he went back to What, paired with a few of Bakugou’s favorite words.
Izuku addressed the crowd. “It’s the only theory I can think of that makes sense. His quirk, if it even is a quirk, doesn’t behave by the same rules that we all know. He doesn’t recognize the number one hero, nor has he recognized any other heroes. His ship resembles something from a historical film more than anything on the ocean today, despite its enhancements.”
He directed his speech to Ace, who was just as stunned as the rest of the crowd. “Where were you when you were transported here, Mr. Ace?”
“I… I was on the Grand Line. In the New World. What do you mean other world?”
Izuku nodded. “I thought so. You’re in another world, Mr. Ace. One more modern than your own, where piracy has largely faded into history. There is no ocean here called the Grand Line. We do have ambition, but it is not a physical force. Clearly our worlds run on different rules.”
“I-- okay, wow. That’s a first even for me. That explains the bystanders. I thought you guys just had a lot of minks living with you.”
One of the heroes stammered out an answer. “W-Well, since the advent of quirks, the populace has grown increasingly varied…”
Ace cocked an eyebrow. “Really? I mean, the animal heads and the other changes are new, but other than that most of you are pretty samey-looking. I don’t see more than two or three people above ten feet here.”
Aizawa cleared his throat. “Clearly another difference between our… realities… that we don’t have time to get into.” Izuku looked like he wanted to say something, but a glare from Aizawa, now goggle-less, stopped him from saying anything. “If we’re done fighting, can you go back the way you came?”
Ace looked to the fog. “I’m not sure if it will work.” he demurred.
“Do you really have another option?” replied Aizawa.
Ace looked at the fog, then at all the heroes surrounding him. “Well, I could stay here, but I’ve got family back on the Grand Line… eh, I’ll chance it. I’m sure it’ll be okay.”
With that, he walked over to the waterfront, casually as you please. The heroes stared after him, many still shocked silent by the events of the last minute or so. He turned to face the crowd, standing on the ledge above the water.
“I gotta say, pretty good fight though. Especially you kids. Nice trick with the iceberg, Two-Sides, I might have to steal that one. Oh, but you might want to appoint someone other than Fireface as your welcoming crew. He sucks at it.”
At that, he jumped backwards, and moments later his small ship was speeding towards the odd fog cloud.
He was chased by Endeavor’s voice, as he shouted challenges to the retreating pirate. He didn’t even look back once.
Five minutes later, the fog was gone. Tokyo returned to normal-- well, for a given value of normal, that is.