A/N-Shoutout to John_A_Mandrake, Garret_Small and seydeen for the powerstones!!
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"You ARE a monster." Carter smiled at that, unsettling Nine and the others as they could see the gleam of teeth as big as their forearms. "Maybe, maybe not." Carter mused almost mockingly. "What matters right now isn't what Stain warned you about, or what Tomura demanded you do, but the fact that I can heal you right now, permanently."
Nine shook his head, "No, I would rather take the boy's quirk that accept whatever deal you have cooked up." Carter sighed as he broke a piece of wall and turned it into a piece of paper with a number on it. "Should you reconsider, call me." He said before taking to the air once again.
The rest of the night was spent helping Izuku enact his plan. After Katsuma woke him and Katsumi up, they and the rest of the class debated on what to do and finally came up with a decent plan. The were going to move everyone into a castle on Mount Shiroyama, a smaller island connected to Nabu Island.
By moving them there, they could hold off the villains better since they had the terrain advantage while giving the people time to escape through the caves. So that's how Carter spent his night, helping move civilians into a castle while keeping an eye out for Nine just in case he decided to attack early.
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Feeling generous for once Carter made breakfast with the little food they had the next morning, sprinkling in a few spells that made the food more filling for the day ahead of them. As they went to their spots he saw Nine, Slice and Chimera approaching from a distance.
When they got in range Aoyama opened up with his ultimate move 'Supernova' unleashing a barrage of lasers forcing Nine to throw up a barrier as Slice and Chimera went around either side of him, just as planned.
Waiting for them were two cannons that Momo had made using the last bit of her quirk before eating breakfast, firing them at the exact spots Izuku had specified. One destroyed the ground beneath Slice dropping her into a dark cavern where Fumikage and Mina were waiting, as the other direct impacted Chimera throwing him towards a waterfall where Shoto, Ida, Eijiro and Tsuyu were waiting.
With his backup gone Hanta and Ochako used their quirks to hurl boulders at Nine, forcing him to dodge after the first smashes through his barrier. He isn't passive though as he fires lasers from his fingers forcing them back as they fall back to a trap they'd set during the night.
Once he was in the right position, Hanta and Ochako collapsed a mountain of rocks on him, as Mineta rushed over and threw sticky balls into the pile, sticking the rock even tighter together. "Did we get him?" He asked massaging his scalp.
Boom CRASH
The rocks didn't hold for long as Nine bursts through sending boulders flying as He knocks Mineta unconscious. Seeing things go wrong Izuku and Katsumi rush in as Hanta grabs Mineta and yanks him away from Nine as Ochako tries to touch his back to get him to float away. She's just withing reach when several large dragon heads burst from Nine's back and slam her to the ground before Izuku kicks Nine away.
Seeing how Nine is starting to be more of a danger to the student rather than a good training tool, Carter decided to step in as Katsumi blasts Nine while Izuku checks on Ochako. BAM Not reacting fast enough Nine gets launched by Carter as he kicks his side, now in his human form. Seeing him take to the field, Nine decided to put more effort in as he calls down a colossal bolt of lighting, as Carter kicks Katsumi to the side right before it hits.
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As this is happening, Slice is barely holding on as a dark boosted Fumikage gives Mina several openings while keeping Slice suppressed. Taking one Mina is able to burn a good portion of Slice's hair as she retaliates fiercely, Dark Shadow covers Fumikage and tries to do the same for Mine but is too late as a projectile slashed against her skin, drawing blood.
Fumikage flew into a rage as he and Dark Shadow unleashed their fury upon Slice, as they raged the cavern around them started to collapse, unable to keep up with a dark boosted enraged Dark Shadow, Slice was knocked unconscious before Fumikage flew over to Mina and covered them in shadows as the cavern fell around them.
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Over at the waterfall, Shoto and his group were having trouble dealing with Chimera.
Tsuyu had drug him into the water several times, but each time Shoto froze it he would just smash it to pieces. Kirishima and Ida kept the pressure going as Chimera felt his body start to slow down, feeling sluggish as the student enacted their plan.
Using a toxic mucus that Tsuyu's quirk secreted, they had coated their hands and legs with it and the constant hammering of Chimera was finally starting to catch up. With him now weaker Tsuyu was able to submerge him completely in the water as Shoto froze it over.
He was too slow however as Chimera burst through the ice, several meters taller as a wave of flames burst from him, forcing them back as Shoto made a wall of ice to shield them. "Guys I got a plan!" Kirishima said as Chimera picked himself up.
Not giving him time to get up Ida circled around as Eijiro rushed him head on. "BURN!" Chimera roared as flames poured from his mouth. Facing the wall of flames Eijiro felt no fear as he used his quirk to the fullest. 'UNBREAKABLE!'
After training hard for the time that Carter was gone, he was able to harden himself enough to withstand half an AP shot from Katsumi, that gave him the strength to hold on as the flames tried to burn him to ash.
Seeing his shot Ida used his signature move as he blazed forward. 'RECIPRO BURST!' Using his speed and mass he slammed into the back of Chimera's knee, toppling the villain as Kirishima fell unconscious.
Quickly Tsuyu wrapped her tongue around Chimera as many times as she could as Shoto flew forward and landed on the top of his head. "SUB-ZERO!"
It worked, he had frozen Chimera into a solid block of ice. Shoto helped move Ida and Kirishima out of the water and promptly fell unconscious himself as Tsuyu massaged her sore tongue.
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KRA-KOOM!
The ground shook as Katsumi landed next to Izuku. Even meters away the static in the air from such a blast woke Ochako up as Nine stared intently at the spot his lightning hit.
"Not bad, I almost felt that." Carter's voice mocked as he flapped his wings once, sending the dust flying to show him unscathed, though he was covered in his scale armor. Seeing him in such a pristine state sends chills up Nine's spine as he put quite a bit of effort into that blast. 'Stain was right, this kid is no hero.' He thought as he dodged to the side before countering.
As they fought, Nine became more and more wary of Carter. Not because of his overwhelming power, no he already knew that he could end this fight in one hit if he really wished. What scared him was how much he was able to restrain himself, and the amount of control and skill he wielded.
Since he could never use much of his quirk without damaging his body, Nine had always trained control to a fine point, although he could beat his foes with raw power, he used technique and skill since it would delay the inevitable just a little longer.
Carter seemed to take that to the extreme. Nine had seen the footage of All Might fighting All for One, and how Carter had stood toe to toe with two legends and walked away unscathed. Yet rather than tank every hit, he fought smart, blocking and dodging hits so he could deliver devastating counters that shook even Nine's enhanced body.
WHAM!
Carter threw in a feint that Nine fell for before he punched him back several meters, his feet dragging across the ground as he skid to a halt panting.
"You fight well, trained, and enhanced most likely. A shame your own quirk is against you." He said softly, as if consoling him as he calmly walked towards him. Before Nine could do anything, Carter shot forward seizing him by the neck as he lifted him into the air.
"Grk! L-let me go!" Nine choked out as Carter leaned in and whispered in his ear, loud enough for only the two of them to hear.
"My offer still stands, be healed, and gain a chance to shape this wretched world for the better. Or you can keep playing around with Shigaraki and Stain, your choice." Nine didn't answer as he clawed at his hand, trying get get the air he desperately needed to survive.
Rolling his eyes Carter released Nine as he fell to the ground gasping for air. Seeing he was busy trying to breath Carter went over to Izuku, Katsumi and Ochako who was looking at him funny. "You guys need to do some better training, this guy should be easy."
Ochako snorted at that, other than freaks of nature like Shoji and Carter, she was the one lifting the most weight in the class. Katsumi gave her a look that said 'the fuck is up with him?' As Izuku tried to defend them saying that they were doing their best.
Carter rolled his eyes as he felt Nine's aura change, becoming much stronger and more chaotic. "If you were truly giving it your all, he wouldn't be powering up right now." He said jamming a thumb at Nine as he stood up, dark clouds started to roll in as they got ready for a fight, Carter stepped back as they rushed him, ready to see if they would finally start fighting like their lives depended on it.
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Although Carter had left to go dig Fumikage and Mine out of the cavern, Nine still wasn't able to relax very much as Izuku and Katsumi kept the pressure steady. Having handed Mineta over to Shoji, Hanta and Ochako went back to hurling boulders at him as he started to use more and more drugs to keep stable.
After a particularly large boulder hits Nine and pushes him back a few meter, the students rush back to a fall back point and catch their breath. They don't get to rest for long as Nine is back, now closer than ever to reaching his goal.
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After depositing the injured Fumikage and Mina with Momo and the other students still with the civilians, Carter went to go check on Shoto and his group.
Reaching them he was mildly surprised to see the massive statue of ice that Chimera was trapped in. He felt mildly disappointed to see all of them except Tsuyu pass out out though.
"Are you ok, do you need me to carry you as well?" He asked as she shook her head saying she could manage, but would appreciate a ride back. Deciding to be lenient for once since she proved to be better than the guys, he turned into his Nightwing form as she sat between his wings. The guys however would end up waking up inside the talons of a massive dragon.
They yelled like little girls, but Tsuyu's laughing shut them up quick as Carter arrived where he had last left Nine and the students.
It was a mess, dark clouds loomed overhead as lightning flashed ominously, "Stay here, it'll be safer." He said setting them down as he rushed into the place where he could feel several strong auras duking it out.
Bursting into the castle he found Izuku and Katsumi struggling to get up as Nine held Katsumi by the head, ready to take his quirk.
Nine felt elation as he prepared to take his own life into his hands at long last, before that blasted voice came back. "I leave for five minutes and you can't even deal with him?" Nine spins throwing up a barrier, it's useless as Carter's fist shatters it and buries itself in his stomach, sending him crashing into a wall as he catches Katsuma to keep him from falling.
"Good job kid, who were brave." Carter says not taking his eyes off Nine as he sets Katsumi down, he runs over to check on Izuku and Katsumi as Nine pulls himself from the wall.
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Seeing Carter and Nine start to fight for the third time, Izuku and Katsumi desperately want to get up and help, but their bodies won't move. As the fight goes on though, they realize they aren't needed as blows that shook their bodies didn't even seem to register for Carter.
Though he and Nine were mostly after images, the little they could see showed Nine to be in a much worse state than before. He's also more powerful as the blows from them fighting is enough to rattle them from where they've struggled back up to their feet.
'We have to do something, anything!' Izuku thinks as his minds thinks of OFA, and how maybe Katsumi would make better use of it than him.
KA-BAAM!
The ground and walls shake as Nine is launched back outside, with Carter looking mildly annoyed. "I'm going to deal with him, don't you dare do anything stupid boy." He says looking right at Izuku before he chases after Nine, leaving Izuku and the others to pick themselves up off the floor as thunder rolls.
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"Get out of my way!" Nine roared as he blasted bolt after bolt at Carter, both doing nothing as he closed the distance. Barriers held just long enough for him to throw up another as Carter kicked him around like a ball.
Ka-BOOM!
Another massive bolt splits the sky as Carter tanks the hit. Nine is barely holding on having already used the stash of drugs he packed, as well as the power enhancing quirk that was the only thing keeping him alive at the moment.
"Before you were useful because of you ideals, and could give those idiot children another reason to grow stronger, but now your just a nuisance." Carter said as Nine called forth the largest storm he had ever made. Even the heroes who were coming to help after not hearing from the students could see them fighting as they pushed harder to get their in time.
"I won't let you stand in my way." Nine yelled as a massive bolt of lightning crackled above, waiting for its moment. "Not you, not Shigaraki, not the Doctor, not even ALL FOR ONE." Seeing such a massive display of power, Carter smiled and decided to give some effort as well, as he called forth the flaming gauntlet he made in the last world.
"DIVINE CATACLYSM!" Nine roars as a bolt of lightning, as thick as his dragon from streaks down to Carter. "Inferno Lance." He says calmly, like he's telling someone how his day was, as the two beams of energy, one plasma, one electric, collide head on.
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The ground shook for a few minutes before Izuku and Katsumi ran out to find utter devastation.
The ground was barren, with black scorch marks from Nine's lightning, and craters from the hits he'd managed to avoid. They didn't have to go far to find Carter, and what was left of Nine, deep in a crater that was red hot.
"OH, you finally picked yourselves off the ground." Carter said noticing them before kicking them out of the way. WHOOSH click click "Stay down." He said calmly as he shot forward and punched what seemed to be air.
Until it shimmered and a dark scaly figure launched itself at them, Carter pushed it back but it seems that he wasn't the target as the creature punched his side making him slide back as it lunged for Nine. Izuku and Katsumi tried to get in its way but it knocked them aside with ease before scooping up the frail and dying Nine and taking off as heroes led by Hawks arrived.
"Who the hell was that?!" Katsumi yelled as Izuku started murmuring about all the possibilities. SMACK "Don't overthink it, probably just the League or whoever made him." Carter said as Izuku rubbed his head, 'Not bad, she can be useful, but he remains to be seen.'