It's been a day since the events of training camp. Izuku was forced to stay in the hospital one night so they could make sure he was ok. The next day Izuku was sitting up on the bed and his attention was caught by some talking outside the door. This was until the door to the room opened revealing Shoto poking his head through the door.

Shoto: “Oh Izuku you're awake”

Izuku: “yeah”

Before Shoto could say anything else he was pushed out the way as Uraraka barged past him and into the room carrying a duffle bag

Uraraka: “IZU!!!”

She immediately ran up to him and pulled him into a quick hug which he returned after a couple of seconds they separated. Uraraka sat next to him on the bed, dropping the duffle bag next to the bed as the rest of the class came in.

Izuku: “hey guy’s is everybody alright”

Lida: “yeah we’re fine Jiro and Hagakura are still recovering from the gas but they should be fine and Yaoyorozu also got hit hard on the head and is still hospitalized here. Apparently she regained consciousness yesterday”

Izuku looks round the room at everybody their before realizing katsuki was missing

Izuku: “hey where's katsuki”

Shoto: “i'm sorry to say this but your sister was~”

Izuku: “taken by the villains yeah i know”

Uraraka: “well bakugo tuck Izumi's abduction harder than anybody else he's somewhere trying to get his head straight”

The class sat and talked for a while till the class decided to leave, only leaving Izuku and Uraraka in the room. After the class left Izuku immediately starts trying to get out of bed as quick as possible only for Uraraka to try and slow him down

Uraraka: “Izu slow down for a sec”

Izuku: “i have to get back to the cave”

Uraraka: “yeah i know but you might need these”

She hands him the duffle bag when he opens it he saw some of his cloths

Uraraka: “i figured you would want to get out of here as soon as you could”

Izuku: “i’ll meet you outside”

She gives him a thumbs up before leaving him to change. After a couple of minutes izuku leaves the room and meets up with Uraraka outside the room. They both start making their way out of the hospital until they hear momo’s voice coming from a nearby room. They both head over to the door and look into the room to find momo talking to all might and detective Tsukauchi.

Momo: “i managed to attach a tracking device to one of the villains”

She holds up a small device

Momo: “when the device is activated it will seek out and connect to the tracker and receive the trackers location pleasure use this in your investigation”

She hands the device to all might 

All might: “thank you young Yaoyorozu this will help us immensely”

Momo: “i just wish i could do more especially with a classmate in danger”

All might: “please don't worry just leave the rest to us”

After hearing all this Izuku and Uraraka quickly leave before they could be noticed and make their way out of the hospital. Before they could get any further they were stopped by Aizawa calling to them. When they looked towards him they saw him leaning against Izuku’s car.

Izuku: “you better not have chipped the paint”

Aizawa: “i know how to drive problem child”

Izuku: “how did you even get my keys”

Aizawa: “you left them at the dorms”

Izuku: “just give me my keys”

Aizawa tosses his keys before they all get into the car. As soon as Izuku gets into his car he gives Aizawa an annoyed look as he adjusts his seat. Before they head towards the cave after a while they pull up to the penthouse building.

Uraraka: “i thought you said we were going to you know the batcave”

Izuku: “we are”

Without saying another word Izuku walks into the building being followed by Aizawa and Uraraka they all pile into the elevator and head to Bruce's penthouse. When they make it to the penthouse they both follow izuku into the study room before ever of them could say anything Izuku walks over to the side of one of the book shelf as soon as he stood there a blue light comes out of the shelf and starts scanning Izuku’s eye’s as soon as it was done scanning his eyes the wall closest to him went inwards and then separated revealing a elevator. Izuku steps in before turning toward them

Izuku: “you two coming or what”

With surprised faces they both head into the elevator as soon as they were in the doors closed and the elevator started descending after a couple of seconds the elevator stops and the doors open. As all three step out

Izuku: “Ochaco Aizawa welcome to the batcave”

They walk further into the cave. Izuku looks at Uraraka’s excited expression as she looks round the cave when they get close to the computer Ace got up off the ground and ran towards them before circling both Izuku and Ochaco. immediately they starts petting him

Izuku: “hey buddy miss us”

Uraraka: “so this is were you two go when i'm not around”

Ace barks almost as if answering her. As this was happening Bruce turned his chair to face them.

Bruce: “i see you brought company with you”

Izuku: “Ochaco Aizawa meet bruce wayne the original batman”

Uraraka: “yeah we know or at least i know”

Izuku: “how?”

Uraraka: “well when i found out you were batman i kinda made the connection that you started working for mr wayne the exact same time you first started as batman”

Aizawa: “plus mr wayne would be around the same age that the original batman would be now”

Bruce: “very good detective work but just call me bruce both of you”

Aizawa walks up to bruce and holds his hand out to shake bruce's hand

Aizawa: “it's a honor to meet you”

Bruce shakes aizawa’s hand as Izuku gives Aizawa a confused look before walking up to the the computer

Izuku: “ok we should properly get to business”

Bruce: “i've been collecting everything related to the the villains trying to harrow down where their base of operations would be but nothing concrete yet”

Izuku: “i might have a easier way me and Ochaco overheard a conversation at the hospital apparently Yaoyorozu placed a tracking device on one of the villains if we can get our hand on it then we should be led right to them”

Uraraka: “why do we need to steal it”

Izuku: “the device is in all might’s possession and if i know anything it's that no matter what he's not going to let that device out of his sight as long as Izumi is in danger” 

Aizawa: “it might take a while but i should be able to get the device”

Uraraka: “but want the heroes notice its missing”

Bruce: “who said we need to take it here”

Bruce throws Aizawa small bat shaped device

Bruce: “that's a bug place on the inside of the device and when that device connects to the tracker it will send the location to us no one will even have to know that it's their”

Aizawa nodded as he leaves the cave

Uraraka: “so what are we going to do while mr Aizawa is placing the bug”

Bruce: “i'm going to keep oneting the situation just in case the villains decide to do something”

Izuku: “and i'm going to repair the suit”

Uraraka: “so what should i do”

Izuku: “you can have a look around try and get as comfortable as you can in this place”

After saying this izuku heads over to a table and starts repairing the suit while Uraraka starts looking round the cave.

After a while 

Uraraka was looking through all the old mementos of Bruce's day’s as batman as well as some new auditions from izuku’s adventures such as one of shriek's sound discs and Dracula's skull. She carried on looking through the cave until she ended up near the suit cases looking at the original bat family suits. Izuku looked at her and gave a small smile at her amazement and excitement at what she was seeing. His attention was pulled away from her when his phone started ringing, getting everyone’s attention when he looked at who was calling him he saw it was Aizawa immediately everyone in the cave went to the computer. As soon as they got to the computer, they answered the phone and put it on speaker for everyone to hear.

Izuku: “did you manage to bug the device”

Aizawa: “i did…the heroes wanted to bring you in on this”

Izuku: “what did you tell them”

Aizawa: “i told them that i have been in contact with you and that your already on it”

Uraraka: “can we use the tracker right now”

Bruce: “i'm already looking into it now”

Bruce brings up the tracker and starts analyzing everywhere the tracker went, coming up with two locations that the tracker has been most often.

Bruce: “there are two location that the villains have been”

Izuku: “what are they?”

Bruce: “one’s a bar while the other is a warehouse this is also where the trackers signal is coming from”

Izuku: “so one of those location is where we need to go”

Aizawa: “if i chose a location i can form a group of heroes to go after the other location”

Uraraka: “can you i don't know hack into the security cameras and see which location Izumi is in”

Bruce starts hacking into the security cameras of the warehouse only to find that all the cameras have been taken offline. After failing with the warehouse cameras he starts trying to hack into the bar’s security cameras after a little bit Bruce manages to get in and pulls up a live feed of what is happening at the bar. In the bar the group of villains were standing round while Izumi was tied to a chair and looked to have a few more cuts than she previously did. Izuku clenches his fist watching the sense play out. 

Uraraka: “is there any way to hear what they are saying”

Bruce types on the computer and turns the sound. Back in the bar shigaraki had just turned off the tv playing a news report on Izumi’s abduction as well as bad mouthing the heroes for not finding her yet

Shigaraki: “you know is’t funny how heroes can do so much for people sacrifice so much nearly get themselves killed hundreds of times only for one little event to turn the people they protect against them it’s kind of funny if you think about it”

Izumi kept her head down as Shigaraki spoke

Izumi: “go to hell”

Dabi: “Why did the boss's secret partner insist on us kidnaping her anyway?”

Shigaraki: “i don't know i don’t question him”

Back at the cave

Izuku: “Aizawa i'm sending you the two locations form two groups of heroes send one to the warehouse and the other to the bar”

Aizawa: “ok which location should i be expecting you”

Before Izuku could reply to bruce chimed in 

Bruce: “he’ll be at the warehouse”

Izuku looks at bruce with a little bit of surprise on his face

Izuku: “what? But Izumi”

Bruce: “will be fine when the heroes get their but that warehouse is a unknown element whatever is inside could end up being more dangerous”

Izuku was about reply before being stopped by bruce once again

Bruce: “you have to keep your emotions out of this”

Izuku: “yeah i get it Aizawa make sure to send All might and magnetic to the bar”

Aizawa: “alright i’ll inform the group heading to the warehouse good luck problem child”

Izuku: “thanks aizawa”

After saying this Izuku hangs up the phone before heading to change into his suit. He returns back to the computer a couple minutes later wearing the batsuit but with the mask pulled back revealing his face.

Izuku: “while i'm heading to the warehouse one of you is going to need to be on com’s while the other monitors what’s going on at the bar”

Uraraka: “i could keep an eye on the bar while bruce helps you out”

Izuku: “you sure?”

Uraraka: “yeah i'm still kinda new to all this so i should properly let the professionals take charge for a while”

Izuku: “ok but if anything happens contact me immediately”

Uraraka: “copy that”

Izuku reaches back and pulls his mask over his face before heading to the batmobile. As soon as Izuku gets in the batmobile he rockets out of the cave and heads towards the warehouse after a few minutes Izuku makes it to the warehouse as he flies over it he spots a group of heroes and police a fair distance away from it. He puts the batmobile on auto pilot before dropping gout and gliding towards the group he lands on a windowsill slightly above them getting their attention. It took only a second before a female hero walked up to him.

???: “batman awesome hi i'm the pro hero mount lady”

She points towards the rest of the heroes 

Mount lady: “and this is pros heroes tiger, best jeanist and king orca”

Batman: “nice to meet you so what's the plan”

Best jeanist: “we were planning to use mount lady's quirk break down a wall to get in and have the police form a barricade round the hole”

Batman: “so a surprise attack not bad thinking but we should really know what we're getting ourselves into”

Mount lady: “how do you suggest we get intel on what in the warehouse without giving away that we’re here to early”

Izuku throws a com price at best jeanist

Batman: “i’ll scout it out and repot what i find to you thru that while i'm in their get into position and be ready this is most likely going to end in a fight”

They all give him a quick nod before Izuku rockets up and heads to the top of the warehouse before making his way in. He turns invisible. Izuku cuts a hole in a window before climbs through it as he makes it into the warehouse he couldn't see anything due to how dark it was he turns on detective vision. As soon as he was able to see what was around him a look of shock and horror crept on his face as he could see rows upon rows of containers holding nomus immediately after seeing this he contacted the group of heroes outside the warehouse.

Batman: “is everyone in position”

Best jeanist com: “yea everyone is in position what are we dealing with” 

Batman: “nomus properly an entire arm this must be were they manufacture them”

Best jeanist com: “we’re starting the attack now”

As soon as he finished speaking a wall was broken down by mount lady slamming her leg down on it. This action caused all the nomus in the warehouse to be released and start attacking the heroes. Izuku became visible again before helping the heroes fight the nomus.

After a while 

They had just finished up fighting the the remaining nomus when Uraraka come over the prive com’s line sound a bit panicked

Uraraka com: “Izu we have a problem!!”

Batman: “what’s going on?”

Uraraka com: “Izumi and the villains disappeared”

Batman: “what do you mean they disappeared what happened?”

Uraraka com: ”the heroes had them captured and Izumi was free then suddenly some sort of black slime came spewing out of each of their mouths before covering them and suddenly they were gone”

Before Izuku could respond he heard footsteps heading towards them as he looked over. It was a man wearing a black suit along with a mask covering his whole head with some pips coming out of it.

Uraraka com: “Izuku did you hear what i said”

Batman: “yeah we might have a problem here as well help with trying to find them i’ll get back in contact as soon as i can”

???: “well it seems you all have defeated my experiment”

King orca: “stop, don't move!!”

As the man starts walking closer to them best jeanist uses his quirk to manipulate the man’s suit fibers to subdue the man up. Best jeanist tightens his grip on the man trying to keep the man from doing anything until red lightning starts sparking off the man seeing that Izuku immediately ran to cover. The red lightning became quicker and stronger until a large blast of power knocked everybody back while destroying a small portion of the city, sending rubble everywhere. The heroes who had taken the brunt of the force were lying unconscious leaving only a few injured and semi conscious Izuku was hit and pinned by some rubble.

???: “very strong quirk being able to restrain me with my own clothes fibers but that should be expected for the number four hero”

As best jeanist tries to get up the man points at him only for a red laser to fire off the tip of his finger and impale best jeanist in the stomach causing him to collapse to the floor uncounches. Izuku witnessed this while trying to get the rubble off of him. As he manages to get a bit of the rubble off of himself a gagging sound followed by coughing caught his attention. When he looked towards the sound he saw Izumi along with the group of villains from the bar now standing near the man.

Izumi: “Who are you?”

???: “you may not know me but you know of me and i know you Izumi yagi”

Izumi: “what are you talking about?”

???: “i know what power you hold you may call me all for one”

A look of shock and fear came across as she recognized the name

Izumi: “your the one dad told me about warned me about”

All for one: “yes and i know a lot about you and your family”

Izumi: “is that why you kidnap me”

All for one: “me and my partner have taken a interest in you family though i only want my quirk back but my partner has taken a special interest in you brother”

Izumi: “you stay the hell away from him!!”

All for one: “i have no interest in you brother or his secret”

Izuku was getting the remaining rubble off of himself as soon as he heard all for one he started moving faster.

Izumi: “What secret?”

Izuku used everything he had managing to get the remaining rubble off

All for one: “didn’t care to know now if we’re done talking i would like my quirk back”

As soon as he finished speaking all for one lunged forward his hand glowing before he could grab hold of Izumi’s forehead izuku threw a sharp batarang embedding itself in all for one's hand. As Izuku ran towards them. All for one just pulled the batarang out of his hand and used a healing quirk to heal his injury. In the distance all might could be seen diving towards all for one after a couple seconds all might collide with all for one as soon as they made contact with each other a large amount of wind pressure pushing everyone back.

All might: “how dare you!!!”

All for one: “are you planning to try and kill me again”

The two kept colliding together until all for one managed to get the upper hand knocking all might back

All for one: “you’ve gotten weaker all might overexerting yourself fighting, how many longer do you have left until your power is gone forever”

All might: “i'm not going to make the same mistake i did all those years ago, i'm not going to let you hurt anyone i care about ever again”

All might run at all for one throwing a punch at him which was countered by all for one using several of his quirks being able to hold him back. As this was happening the league was making their leave as Izuku ran up to Izumi helping her up

Batman: “are you alright?”

Izumi: “yeah i think so”

Izuku looked back at all for one and all might fight. He watches as all might was overwhelmed and thrown into the sky on a direct course with a news chopper before he hit the chopper gran torino came flying in grabbing him and knocking him away from the helicopter landing next to Izuku and Izumi. All might was starting to resemble in smaller form as he was smaller than before as well as his hair starting do drupe down like it was when he isn't using his quirk 

Gran torino: “are you two kids alright”

Batman: “i am but she still has some injuries that need attending to”

All might: “i need to get back to the fight i'm not letting him get away”

Without saying another word all might charged back at all for one

Gran torino: “i’ll help get her and the heroes out of here”

Batman: “i’ll make sure he doesn't get himself killed”

Torino nodded before moving as fast as he could, getting Izumi and the heroes out of the way. As this was happening all might was punched back hard enough that it caused a large shock wave as well as forming a large smoke cloud after a couple of seconds the smoke cloud died down revealing all for one hovering there while using several strength quirks on his left arm. As well as all might rarely completely out of power revealing his smaller form to everybody. All for one was about to throw another punch only for Izuku to throw several explosive batarang at him as he made his way to all might. All for one was able to block or stop most of the batarangs thrown at him only for one to hit him in as it exploded. It cracked his mask, knocking him off balance. Izuku made his way to all might.

Batman: “you ok”

All might: “fine we need to finish this”

Batman: “how much power do you have left?”

All might: “enough for one last smash”

Batman: “we better make it count”

Izuku starts running toward all for one 

All might: “WHAT ARE YOU DOING!?!”

Batman: “probably something really stupid but just focus on charging up whatever remains of you power we will only get one shot at this and we can't afford to miss”

Before all might could argue any further Izuku rocketed towards all for one making sure to punch him in the face trying to keep him off balance and break his mask even further. All for one fired red tendrils at him acting quickly, Izuku flipped and maneuvered trying to avoid them as much as he could. Not getting any closer Izuku fell back before rocketing into the air he grabbed several explosives out of his utility belt before diving towards all for one. In response all for one fired the red tendrils as well as air bullets at him. Izuku tried to maneuver and avoid being hit. As five tendrils were about to impale him he threw a large amount of his explosives at the tendrils creating a smoke cloud before all fore one could find out what happened Izuku came rocketing out of the cloud with a broken piece of the embedded into his shoulder. As soon as he was close to all for one he threw the remaining explosives into his face. The explosives managed to completely destroy his mask. Without wasting a second izuku somersaulted over all for one as he landed he threw some freeze grenade keeping all for one in place.

Batman: “ALL MIGHT NOW!!”

Hearing this all might summoned some of his remaining power into his legs as he shot toward all for one as he got close he poured all the remaining power into his right arm. He punched all for all in the face with everything he had 

All might: “UNITED STATES OF SMASH!!!”

The power created a crater underneath them as he slammed all for one’s head into the ground knocking him out. As the battle ended all might stude now in his smaller form he changed into his bigger form for only a couple seconds as he raised his fist into the air signaling the battle was over. Seeing this izuku pulled the red tendril that had impaled him in the shoulder gritting his teeth in pain as he did. When he looked back over toward all might he could see several reporters running up to him as some other heroes loaded all for one into the back of a police van. not wanting to stick around Izuku started walking the opposite direction until he felt a hand lightly grab his non injured shoulder stopping him when he turned he saw all might holding his shoulder 

Yagi: “their going to want to talk to the hero that saved the city”

Batman: “i'm pretty sure that was you”

Yagi: “that was us”

Batman: “it doesn't matter anyway there's somewhere i need to be”

Izuku was about to fly off bat as he opens his wings a sharp pain surges through is shoulder causing him to stop in pain for a couple of seconds

Yagi: “are you alright”

Batman: “yeah just a little pain”

After saying this Izuku rockets into the air and starts flying away from the battle sight just as the news reporters caught up to them. 

Reporters: “all might you just fought beside the new batman do you have any insight to who he is?”

Yagi: “i know who he is”

Reporters: “you do?”

Yagi: “yea he’s a hero”

A while later

Izumi was sitting in as hospital room staring out the window until the door to the room opened Izumi didn't take her eye off the window

Izumi: “*sigh* mom i'm fine can you please stop asking”

Izuku: “since im not mom i'm going to ask you alright”

Hearing his voice Izumi head snapped towards him

Izumi: “Izuku what are you doing here”

Izuku: “i came to see if you were ok after everything that happened but if you want me to leave”

Izumi: “NO! I mean please don’t leave yet its just i thought you still hated me”

Izuku: “remember when i said if you ever want to earn my trust it would be through you actions”

Izumi: “yeah”

Izuku: “well i heard what you did saving kota it may take some more time to completely trust you again but you on the right track just keep going”

Before izumi could respond the door to the room opened as inko and toshinori entered

Inko: “Izuku what are you doing here?”

Izuku: “just making sure izumi is alright i'm leaving now anyway i promised ochaco i would take her out tonight”

Inko: “ok we won't keep you”

As he walks past them the pain in his shoulder acts up causing him to groan in pain.

Yagi: “Are you ok son?”

Izuku: “just a little pain”

Yagi’s has a look of disbelief as izuku was leaving the room

Izumi; “see ya later Izuku”

Izuku: “yeah see ya sis”

Hearing this made Izumi wider than she had in several years. Inko smiled hearing this as well until she yagi’s face

Inko: “is everything ok honey”

Yagi: “yeah just thinking about something but it's nothing to worry about”

Back at u.a

Izuku had just made his way to the entrance only to be greeted by Uraraka. They made some small talk as they headed to the dorms. This was until they were stopped by hearing mandalay voice calling to them she was with kota.

Izuku: “hey mandalay what are you and kota here for”

Mandalay: “well since the villains know where we live i thought it would be safer for kota if we moved away”

Izuku: “really how are you enjoying it here kota”

Kota: “....its fine i guess”

Mandalay: “sorry after everything that happened he's still adjusting to everything”

There was a couple moment of silence until Uraraka knelt down in front of kota

Uraraka: “hey”

Kota: “...hey”

Uraraka: “i heard batman saved you you know he save me a while too”

Kota: “he did?”

Uraraka: “yeah the villain inque”

Almost instantly Kota's mood brightened up as he and Uraraka started talking about their experiences and interactions with batman. Seeing this caused both izuku and mandalay to smile as the two of them talked for a while until they separated with izuku and Uraraka going back to the dorms.