Template:Katsuki Synopsis/Final Act

Dark Hero Arc
With Tomura and All For One loose, and the secret of One For All slowly being leaked, Izuku decides to leave U.A. in order to protect his classmates from danger, sending them all personalized letters explaining his departure. This infuriates Katsuki who immediately looks to figure out where he went. He's able to deduce that he and All Might are working together alongside the Top 3 Pro Heroes, and when he, Shoto, and Fumikage are unable to receive any responses from their mentors, it fuels their beliefs.

The three propose their theories to the rest of Class 1-A, who try to understand what all their plan is. Katsuki himself states that, knowing the two of them the best, the thought of him and All Might being together right now is the worst possible scenario so they need to confirm their suspicions. Ochaco suggests taking advantage of Endeavor being a U.A. alumni to learn the truth, and after convincing Nezu, the class is able to corner Endeavor for answers.

After indirectly revealing Izuku and All Might are working together, Katsuki approaches Endeavor telling him that while it may have been the right call, he knows nothing about Izuku; that he's someone who never takes himself into account and always insists he's fine, the same way All Might became the Symbol of Peace. He tells him that he can't let the two of them be together or else he will run himself ragged. Aware that Izuku has already begun to go rogue, Endeavor reluctantly hands over Izuku's GPS tracker to the class, with Nezu giving Class 1-A his support to assist the Heroes to go out and bring Izuku back to U.A.

Class 1-A manage to track down Deku in Kamino, where a villain known as Dictator had been engaging him in battle, using his Quirk Despot to control an army of civilians to dogpile him. Dynamight manages to arrive and using an AP Shot on Dictator, shuts down his Quirk, while informing the rest of the class he's found Deku.

The rest of the class quickly appear, with Shoto and Creati restraining Dictator, while the civilians run off. Deku asks his classmates why they're here, insisting that he's fine, leading Dynamight to mockingly say it's good to hear before asking if he's still smiling now. Deku responds saying that if he is to smile, he needs to keep moving forward, and demands everyone to get out of his way. Dynamight retorts that he should make them, calling him an "All Might wannabe," as the rest of the class stand beside him to stop Deku.

Dynamight taunts Deku's current appearance, how he now looks completely different, also mentioning how he heard he's unlocked the Quirks from the 4th and 6th users now. Deku thanks everyone for coming, before using Smokescreen to make an escape. Uravity recognizes it as the Quirk of the 6th user, as Dynamight uses his Land Mine Blast to blast away the smoke, asking if Deku believes that now h'es one of the big-shots, if they're all just a bunch of "NPCs" to him.

Deku continues trying to make his escape, being tossed from building to building as each of the Class 1-A members attempt to restrain and reason with him, as he refuses to listen. With him about to make a getaway using Faux 100 Percent to blast into the sky, Class 1-A unveil their final plan: combining Pinky's Acidman and Shoto's Flashfreeze Heatwave to launch Dynamight off Shoto's ice ramp-up to Deku, pushing further with Uravity's Zero Gravity. Dynamight blows through the air and admits to himself there is so much he needs to say to Deku, but right now the only one who can withstand such intense speed is Ingneium, whom he launches straight at Deku using his Explosive Speed: Cluster.

Ingenium manages to grab ahold of Deku's hand, who finally gives in as they are released from the air and are caught by Red Riot on the ground. As the rest of the class catches up, Deku still continues to resist and insist it is too dangerous for him to be around everyone. Dynamight approaches him and asks if he remembers what he said when he got stabbed by Tomura during the War. When Deku says he doesn't, Dynamight reminds him that he said "stop trying to win this on your own", and after he said that, he felt he had to tell him that his body moved on his own when he got stabbed.

Dynamight admits he looked down on Deku because he was Quirkless, and therefore he felt he should be far behind him, but the truth was, he always felt he was above him. He says he couldn't accept the way he was, which led to him bullying him over the years and trying to prove his superiority, but after entering U.A., he kept losing, so started trying to understand Deku's strengths and his weaknesses. He proceeds to tell Deku that even if it doesn't change anything, he has to speak his current truth: He apologizes to him for everything he had done to him up until now, even calling him "Izuku" for the first time.

Dynamight's words snap Deku to his senses as he continues that his choices weren't misguided, but he can't handle it by himself anymore, that if he encounters a hurdle, he can rely on his friends to help him, and the only way to surpass All Might is for everyone to protect U.A. and the civilians together. Deku weakly collapses and apologizes for what he said about everyone not being able to keep up with him, which Dynamight accepts as he catches him.

Class 1-A return to U.A. with Izuku, now equipped with the "U.A. Barrier", where they find the front of the school filled with a crowd of civilians protesting Izuku's entry, knowing that he is being targeted by Tomura and believing it will endanger them. The Heroes are unable to get through to the crowd until Ochaco makes an impassioned speech toward the civilians to let Izuku stay, which everyone becomes affected by. During the speech, Katsuki turns to Izuku and reminds him that he and the others will step up for him if he can't handle something on his own.

By the conclusion of Ochaco's pleas, Izuku breaks down in exhaustion and relief, with the crowd agreeing to let him stay and help, as Katsuki, Class 1-A, and the civilians escort Izuku inside. The boys immediately rush Izuku to the bath, stripping and washing him down before getting in themselves. Katsuki yells at everyone to scrub Izuku first before throwing him into the bath straight away, hopping in himself, as Fumikage takes note that even after his heartfelt apology, he still hasn't changed. Katsuki, however, reminds everyone that his goal to become number one hasn't changed, which makes everyone his rivals still, including Izuku, who he tries to refrain from calling him "Deku". Izuku, however, tells Katsuki that he doesn't have to force himself and can still call him Deku.

After getting out of the bath, Class 1-A is visited by All Might, where he and Izuku apologize and make up before he heads back out. Izuku proceeds to fall asleep, while the class discuss what to do about the situation with the civilians. Kyoka thinks about Shoto's words about the evacuees not having a full change of heart yet, dragging Denki, Fumikage, Katsuki, and Momo closer to her, stating that just like the last time there were other people that regarded them with apprehension, they need to do something to reassure them and bring smiles to their faces, just like they did at the Culture Festival. Class 1-A comes back together, as they declare they won't just bring the world back to how it was, but to make it a better place than before, and do it all together.

U.A. Traitor Arc
Two days later, Class 1-A learn that during this time, Tomura had fought American No. 1 Hero, Star and Stripe, and while she was killed during the battle with Tomura successfully stealing her Quirk, New Order, thanks to her actions, the Quirk acted like a virus within his body, destroying several of his Quirks and delaying his procedure by about a week. All Might informs all this to the class, telling them that this is now their perfect time to prepare for the inevitable all-out war.

Katsuki immediately yells at All Might that they've already been preparing, with the rest of the class revealing that since the War, they've continued their training with the Wild, Wild Pussycats, all with the intention to fight alongside Izuku until Tomura is defeated. Izuku says that Katsuki and the others agreed to practice with him to help master One For All, but Katsuki just barks back at him, like he usually does, claiming he only wants to test out his new Cluster moves on him, to Izuku's shock. The rest of the class each respond with enthusiasm as they all prepare to go out and train, with All Might looking on proud and satisfied.

Out in the courtyard, the class trains their Quirks, with Katsuki and Izuku sparring between each other. Katsuki talks about how he's learnt to "build up and release" from their internship, but now he's focused on saving up a bunch of sweat. So rather than one big Explosion, he can create a barrage of explosions at once to power his new Cluster technique. Izuku also realizes that's why he stays in his winter suit, so he can sweat faster.

Denki discusses with Minoru about how with Tomura and All For One currently weakened and Gigantomachia still sedated, the fight should be easier for them, but Katsuki tells them three reasons why they're wrong. First is that even after being able to locate the research facilities and hideouts, the Heroes were never able to track down All For One himself, calling "Ol' Nutsack Face" a champ at "hide-and-seek", so they are unlikely to find him again.

Momo adds the second thing, which is that Tomura was incomplete in the previous battle, and now they're only working with half of their Heroes, which Katsuki agrees with. He says the last point is that the villains will be the ones to decide when the battle starts, as even if the Search Quirk was destroyed, they're the ones with the edge to start the battle, which is why they're all focusing on calling up everybody possible to help.

Shortly afterwards, he and the rest of the class receive the devastating news that Izuku had just captured the Aoyama Family, learning that they have been spies for All For One, and Yuga was the traitor who isolated the class at the U.S.J. and revealed the location of their training camp. Restraining them in the AV room, he and the other class members refuse to back down from the news despite Nezu's request, all in stunned and tears of Yuga's betrayal. Among everyone's intense reactions, Katsuki calmly replies how it's a "small world" another one of them started out Quirkless, referring to Izuku. He listens to Yuga's desperation that drove him to despair, followed by Izuku's pleading to let Yuga still help them, figuring Izuku's plan.

The rest of the class quickly realize that they could have Yuga help deceive All For One and "steer the villains" into the fight, and when questioned considering his betrayal, say they want him to help them so they can more easily move on and forgive him. For his part, Katsuki quips that due to all the things he went through because of him, five good Howitzer blasts will be enough to make them even, which Hanta awkwardly responds to.

Shota then appears on a tablet screen, taking full responsibility and reveals that he has an idea, which Class 1-A, the U.A. Staff, and Police Force hear while the Aoyama Family's ears have been covered. Naomasa then has the Aoyama Family escorted back to their HQ, telling everyone not to say a word to anyone else about the plan, while he and the rest of the class looking on sullenly. Back at Heights Alliance, Katsuki and the class take a breather, before getting ready to gear back up, as he and everyone, with fire and rage in their eyes over the betrayal, prepare to bring All For One down once and for all. He and the rest of his class form their "Search Squad", heading out to hunt down the remaining villains.

Later, Class 1-A return to the dorms, unable to make any progress in their search for the villains. Just as they are taking their break, All Might, Naomasa, and Nezu arrive, informing them all about their secret finalized plans for the upcoming second War. They explain how they believe All For One is keeping watch over them using the Search Quirk, and Katsuki realizes that them running themselves ragged will allow them to draw All For One out more easily, believing them all to be exhausted. In order to catch him off guard, they are going to have Yuga lure All For One to a specific location, and to make sure he can't detect their lies, they are going to use Hitoshi Shinso's newly improved Brainwashing Quirk to get the family to talk without any ill intent in their voices.

The next day, Nezu announces to the civilians that Tomura will make his big move in 4 days, with Class 1-A moving outside of the U.A. barrier to began prioritizing their safety. The students say their goodbyes to everyone, with Katsuki saying goodbye to his family members, though his mother was very persistent over his cocky attitude, much to his annoyance. He moves out of Heights Alliance and into its upgraded makeshift fortress called "Troy". Inside the dorms after unpacking, Katsuki accompanies Eijiro and Tenya into Shoto's room to check in on him. Shoto thinks about Toya and how he doesn't even know his favorite food, which Katsuki quips is probably udon, leaving Shoto to respond he wouldn't mind making him sit down to eat with him sometime.

Final War Arc
As the Final War begins, Katsuki remains with the rest of Class 1-A until Izuku makes contact with Yuga at the location on the outskirts of the Troy dorms. All For One is successfully lured out, and using Search to sense that no other Heroes are around, summons the Paranormal Liberation Front to overwhelm Izuku. Just as planned, all the Heroes themselves are warped to the battlefield thanks to Neito Monoma copying Kurogiri's Warp Gate, and begin their all-out assault.

The "Troy" defense system is activated, causing gigantic metal barriers to rise from the ground and trap the villains. They are able to break free, but the delay gave the Heroes just enough time for the next part of the plan: to push all the villains into individual Warp Gates to separate them. Katsuki fires a barrage of AP Machine Guns to force the villains back, as he and Izuku prepare to follow suit into one of them. However, suddenly, Izuku is caught off guard when a whip from Himiko Toga grabs onto him, dragging him into another gate, leaving him confused. He enters the Warp Gate, sending him to the now flying U.A. fortress, where Tomura Shigaraki also is, exclaiming to Best Jeanist that something went wrong and Izuku isn't there.

Now within the extensive barrier, Katsuki, Tamaki, Nejire, Edgeshot, Mirko, and Best Jeanist prepare to fight Tomura, even despite Izuku's disappearance. Tomura starts to attack, but finds himself repelled by the fortress, and an electrical barrier surrounding them, as they reveal that the Floating Fortress was designed to specifically take Tomura down, alongside the amount of heroes cooperating within to maintain it. Tomura prepares to attack the arena with a shockwave, however Katsuki mockingly reminds him about what happened in Jaku, revealing that outside the arena, Neito has him in his sight using Erasure to erase his Quirks once again, accompanied by Eraser Head and Manual.

Ultimately, the plan is still at a disadvantage without Izuku there, and even worse, Tomura's left hand suddenly begins to transform into a monstrous blob of fingers. Katsuki is unable to explain the nature of the attack to Mirko, just as a constructive mass of fingers is directly thrown toward her. Although Mirko is able to survive the attack, the grotesque swarm of fingers from Tomura is revealed to be the "growth" from the body, just as is the case with his hair or nails, making his body trying to adapt to his ever-evolving Quirks, the form leading to the next step of their superhuman society: Doctor Kyudai Garaki's Quirk Singularity.

After Katsuki and Mirko both make it out of the attack range to regroup, the two proceed to argue with each other over who's in charge, until Best Jeanist tells them to stay focused. The Heroes all figure that they can't warp Izuku to the U.A. Flying Sky Fortress, as Neito is unable to use two Quirks at the same time, so activating Warp Gate again would require at least ten seconds without Erasure, and the moment Erasure is undone, Tomura will be able to use Decay through each of his endlessly growing wave of fingers, finishing them all. Despite the circumstances, Katsuki and the rest of the Heroes are determined to fight and defeat the new Tomura, even without One For All.

During his fight with Tomura, Katsuki overhears the news that Shoto has defeated his most powerful adversary, his older brother, Dabi. He laughs with confidence that Shoto was able to defeat him, giving the heroes the will to continue on fighting.

Unfortunately, the battle against Tomura remains at a stalemate as the endless wave of fingers still rampage throughout the arena, destroying everything. The heroes fighting against Tomura are having the hardest time trying to strike back or avoid the endless finger regeneration attacks. Best Jeanist tells everyone to keep moving and not let the fingers swallow them up so they can reach the main body.

Tomura monologues that it's because of the All For One Quirk settling into his body, that the various Quirk Factors combine and mold the body into its ideal form to handle it. He declares that with the body and its power, he will create a new world, either of his own or beyond him, and with the world already so split, all that awaits everyone is destruction, and all it does is give rise to incomprehension, lack of understanding, and rejection. He states that under his rule, all the exploited class will be equal, and asking if world peace isn't what the Heroes want.

Katsuki responds that, even though he doesn't know if he's currently Tomura or All For One, he has grown tired of hearing them talk endlessly ever since the Kamino Incident, all the while readying up his new item from the support course, the "Suppressive Heavy Mobile Unit: Strafe Panzer". Using the sweat he stored up from evading the entire time, he unleashes a wide range of Explosions all over the arena, declaring they'll destroy the main body together. He thinks about how Neito and Shota are using Erasure to erase Tomura's Quirks, Denki and the others are using their Quirks to power the Fortress, and Momo and her crew are making sure they still have a floor to stand on.

He then begins to think about Izuku, and Tomura's words about not understanding leading to rejection, telling him that he's already taken it to heart. Unleashing an Explosion that destroys most of the fingers, Katsuki believes he has already taken a step in progress, and knowing people who are trying to push themselves forward, so has no need for anything he's trying to say. He rams toward Tomura, decimating every finger that tries to go to him, and unleashes his Ultimate Move, Howitzer Impact: Cluster.

Ultimately, despite powerful the explosion blast Tomura took to the face, Katsuki was still powerless against Tomura as the villain managed to crush his arm and badly scarring his right side of the face, telling him that's why it would still fail against him. He continues to reiterate what he told to him last time, that he has no more interest in him, unleashing another wave of fingers that Mirko, Best Jeanist, and Edgeshot attempt to stop. Tomura mocks them, asking who thought it was smart to try and get up close, knocking Dynamight to the side and trouncing the three with his "All Might-level" power.

Katsuki attempts to recover, but he is severely wounded, balking at how vast the gap of power really is between them. Tomura looks on toward him, saying that it wasn't his thoughts or feelings that interested him, and that the only thing that catches his interest is that he's closer to Izuku than anyone else. Shota asks for Izuku's status from Mandalay, but she's unable to reach him, as the electromagnetic waves are messing with their transmissions. With Tomura ready to finish him off, Shota calls out to anyone to save Katsuki, as he still needs to graduate from U.A. so he can become the Number 1 Hero.

Katsuki is helpless as Tomura stomps his head to the ground, realizing that Izuku was supposed to be there as well, expecting he'll arrive soon. Katsuki tries to resist and attack again, but is kicked up, his last Grenadier Bracer destroyed, and grabbed by the throat, with Tomura saying it's good his Quirks are erased since it means he'll leave a corpse behind. Remembering back to how enraged Izuku became when he stabbed Katsuki during the War, he knows it'll make a lovely present for him. As the endlessly growing fingers proceed to consume him, Tomura taunts him, telling Katsuki to face reality that even after all the time he has looked up to wanting to be like All Might, no matter how hard he tries, he'll always be in Izuku's shadow.

Nejire then appears, unleashing a Nejire Wave: Pike attack straight toward Tomura, but he puts Katsuki in front of him, forcing Nejire to alter the trajection last minute. With his back turned, Tamaki stabs Tomura in the back with his Vast Hybrid: Octopus Mirage and Scorpius Toxin combo, injecting venom into the villain's back. However, Tomura simply grows a mouth that spits the toxin out, which is followed by even more mouths growing from the finger waves.

In the chaos, Mirio uses his Quirk to retrieve Katsuki, tossing him to Best Jeanist for safety while he and the Big 3 continue to engage Tomura. Best Jeanist takes Katsuki to the side, intending to sew up his arm since they still need his fire power. Seeing Katsuki's face of near defeat, he reiterates his concern, and that they'll all deal with it somehow, even though his previous experiences fighting Tomura won't help him anymore. However, Katsuki revealed something else about Tomura, pointing out "right side finger feint", causing Best Jeanist to realize that even after all of he just endured, Katsuki is not finished yet, with flames of determination and rage in his eyes.

"Tomura" tries to make his way to Katsuki to finish him off, but the Big 3 continue their assault to distract him and Best Jeanist prepares to protect Katsuki. "Tomura" is able to deal with the Big 3, so turns back to face Katsuki, finding that even with the huge amount of damage done to his body, he manages to stand up despite all of Best Jeanist's pleas to stop, telling Izuku he has to win.

Katsuki blasts toward "Tomura" able to use his Explosions speed to successfully dodge each one of his attacks. He thinks about how his Quirk lets him detonate his nitroglycerin-like sweat, and that the Cluster technique had created a side effect he was unaware of, the accumulated spheres of sweat being forced to disperse across his whole body. This allows him to detonate that sweat within his own body and gave him burst of speed but also bore a heavy burden on his body. With his body aching away, Katsuki realizes that this was the path Izuku was walking all this time, as he begins to question whether he could still catch up to him.

Just as "Tomura" is about to hit him with a direct attack, Katsuki appears in a white void, faced with All Might's visage, telling him that ever since they first met there was so much going on that he missed his chance to ask him, pulling out his All Might trading card and lamenting on never getting his signature. At that moment, "Tomura" seemingly kills Katsuki, delivering a heavy punch right on his chest, causing his heart to burst and leaving him fatally wounded, despite all of the combined efforts from the Heroes to recover him. Best Jeanist screams out about his heart as his bloodied body lies lifeless on the ground with a hole in his chest.

In the aftermath of Katsuki's supposed death, the Heroes present are completely horrified of what happened to him. Neito exclaims in disbelief, Best Jeanist observes that his heart was ravaged and has no more pulse, and Mirio is enraged at failing to protect him. "Tomura" taunts Eraser Head, saying that his death is his fault, and for putting so much responsibility on his shoulders while standing on the sidelines, asking who of the remaining Heroes is next.

Despite Katsuki's tragic demise, the Heroes refuse to give up on him, as Edgeshot vows to save his life by repairing all the damage as much as he can while performing CPR inside of his heart using his Ultimate Move: Zenith. The Heroes proceed to do all they can to protect Katsuki while Edgeshot repairs his heart, while "Tomura" angrily tries to stop them from fixing what he "destroyed". He eventually is able to decimate nearly every other hero there, but they are able to keep their hopes up thanks to Izuku's return.

Upon arriving, Izuku goes into shock upon seeing Katsuki's bloody body lying there. Seeing all the other unconscious Heroes sends him into a further induced stress, causing his Quirks to spiral out of control. "Tomura" attempts to take advantage of his unstable state of mind, but Mirio is able to calm him down, telling him that Edgeshot is saving Katsuki's life, so they need to keep fighting because they haven't lost anyone yet. Izuku calms his nerves and entrusts his hopes while he engages "Tomura" in a fated battle, while Best Jeanist and Mirio try to escort Katsuki's body and the rest of the unconscious Heroes out of the way for safety.

Over the course of the events of the War, Izuku ends up battling Tomura outside U.A., while several factors result in the floating structure nearly being on the verge of plummeting, but being saved by Gentle. Eventually, All For One arrives in the vicinity, with the intention of transferring his copy of All For One to Tomura, thus solidifying his control over the body. After a hard-hitting third battle against All Might, All For One emerged victorious, leaving the former Symbol of Peace now completely at his mercy.

Due to keeping his grip on Tomura, Izuku is unable to do anything but watch as Gentle and the American fleets fail to save All Might, while All For One carries his body over his head, ready to rip him apart in front of everyone watching the currently live broadcast feeds of the battle. As Izuku desperately pleads to himself for someone, anyone, to save him, just above U.A., Katsuki, alive and kicking once again, emerges from the smoke and shadows. He looks out towards the edge of U.A., where he and an astonished Izuku exchange glances toward each other.

Despite being critically wounded, Katsuki remains determined to save All Might from his grisly fate. He jumps off and blasts downwards toward Izuku and Tomura with his Explosive Speed. Izuku realizes what Katsuki is trying to do, and while still keeping his hold on Tomura with Blackwhip, reaches his arm out, grabbing Katsuki, and the three begin to twist. Within those few moments, Izuku activates the Second User's Gearshift Quirk on Katsuki, who in conjunction with his Cluster technique after being thrown, is able to barrel through the skies at insanely, blistering speeds.

As Katsuki continues to blast himself forward, all the hopes and prayers of everyone wishing for All Might's safety seem to be propelling him faster, as the wind gives him an extra push. During all this, he recalls his own insecurities about his strength and being the one who put an end to All Might, and so refuses to let All Might down again. In the blink of an eye, Katsuki defies fate and successfully steals back All Might from All For One's hands, ripping them apart in the process. With All Might safe and secured, Katsuki yells out loud that they're going to win.

Katsuki continues blasting himself forward while carrying All Might, landing on a nearby building. All Might asks if he's okay, and Katsuki bites back that it's his line, but suddenly coughs up a lot of blood. Edgeshot re-merges from his chest wound, now just the size of a thread, saying that it's his line to ask. He explains he was forced to expel the blood within Katsuki which should now grant him some relief, but he's still in constant pain after fixing his organs. He further explains how he used his body to mend his organs and broken bones with knots using his "Hidden Hakamada Style", so the repairs won't come unravelled, however reminds him that he will still deal with blowback if he tries to move as his body needs rest. Katsuki is grateful and thanks Edgeshot for saving him.

However, Edgeshot states that he simply held him together, revealing that despite successfully restarting his heart and lungs, he wasn't able to return him to life. His Zenith Ultimate Move was slowly eating away at his own life, making him reach his limit when he found tiny beads of sweat Katsuki produced moments before his death flowing through his bloodstream which helped resuscitate him. He states that while he only held him together, what brought him back was the power he's honed.

Katsuki turns to All Might and asks who the glowing kid is, assuming he was going to fight All For One, which All Might reveals is in fact him. Due to still being paralyzed by Bloodcurdle, he asks for Katsuki's arm, and hands him over the remaining bits of his gauntlet to act as a brace, the "Great Explosion Murder God Dynamight". All Might wishes he could give him more, as he collapses, and Katsuki responds with a smile.

While the villain is distracted, Katsuki returns to the fight and attacks All For One by grabbing his face, shouting that *he's* the final boss. In that moment, Katsuki unleashes a devastating explosion at point blank, declaring that if One For All couldn't keep him in the ground, they'll finish the job.