After a couple of hours, Stain can be seen in Hosu, perching on a water tower looking over the city. A portal opens up behind him as Shigaraki and Y/N (in his outfit) step out.

Shigaraki: Hosu City looks nicer than I expected.

Y/N: So, what are you gonna do now?

Stain: I'm going to reform it. In order to do so, blood must spill.

Y/N: Sounds kinda edgy.

Kurogiri: You have a clear goal. Your dedication is admirable.

Stain: Ahh finally someone who understands.

Shigaraki: I get the feeling that you enjoy picking on me.

Y/N: I know I do.

Stain: Hero is a title for those who've accomplished great deeds. This city is filled with false champions! All they care about is money and fame! Until this world realizes its mistakes, I will continue my work.

Stain grabs hold of his sword and jumps from the water tower and heads in towards the city, leaving Y/N, Kurogiri, and Shigaraki on top of it.

Shigaraki: He talks all high and mighty and stuff. But he's wasting his time focusing on a small stage. He's so noble I could cry.

Y/N: Can you even do that? Seeing as your face looks like a sponge that hasn't seen a droplet of water in ages.

Shigaraki: Hilarious....

Kurogiri: You shouldn't spurn his methods. The reality is that in all the cities that Stain appeared, the crime rates have fallen. Perhaps because heroes are more conscientious or perhaps out of fear. Regardless he does bring change.

Shigaraki: Oh isn't that just wonderful! Heroes are working because of all those murders! Guess our hero killer is also a hero breeder! This is getting boring. It won't work. We just can't agree on a basic level. And he annoys me.

Y/N: Who doesn't?

Shigaraki: Kurogiri, bring out the Nomus.

He opens a portal below them as three Nomu's come from the portal. One with wings, a much bigger one with no eyes, and a skinner one with four eyes.

Shigaraki: You think you can get away with stabbing me? When I get tired of you, I'll kill you. Whenever I feel like it. Just like that Stain.

But let's make it more interesting. How about I crush your honor and your pride first. What do you say big, bad, Hero Killer?

(time-skip) 

It was now nighttime as Arc, Izuku, Shadow, and Gran Torino were on the train.

Arcturus: Why did we pick the late night run for this?

Shadow: More skirmishes happen during the late night, so you'll have more opportunities.

Izuku pulls out his phone and pulls up his messages.

Gran Torino: You kids these days. You're constantly buried in your cell phones.

Izuku was looking at his texts with Iida and saw he saw he read the message but didn't reply. Which was unheard of as Iida never waits more than three minutes to respond to a message.

Arc and Izuku were more concerned about what Iida could be doing when he specifically chose his internship in the same city where his brother was injured. People then started talking about a building exploding at the distance when the train intercom goes off. 

 "Attention, we'll be stopping the train momentarily. Passengers, please hold onto your seats." The breaks were hit when— 

 *CRASH!* 

 All the sudden, someone was thrown right through the train wall. As they try to get up, they're grabbed on the head by a green creature that looked familiar to the boys.

Izuku: Nomu!

Arcturus: Another one?!

Gran Torino: You two, stay back. Shadow, keep them here.

Acting fast, Gran Torino zooms around and kicks Nomu off the hero and dashes out of the train while holding him. Izuku: Gran Torino! He, Arc, and Shadow look out at the hole and see a large fire happening in the city.

Arcturus: The hell is going on? All the sudden, Shadow's communicator goes off and he checks it.

G.U.N. Operative: HQ to Shadow. We've got multiple attacks of unknown hostiles happening in your area. Pros are on the scene, but the villains are putting them at a disadvantage. Requesting immediate backup.

Shadow: Understood. (ends call) Change of plans, kids. The second phase of training begins here. Let's go!

Boys: Right!

Izuku charges up in his move called One For All Full Cowling and the three run. Arc and Shadow weren't super fast yet, but all kept at a good pace with each other.

Izuku: That thing was different, but not many people look wide eyed with brains spilling out.  

Arcturus: It's just like the Nomu that attacked the USJ. Think they're relatives or from a gang of some kind?

Shadow: With those mutations, more like lab experiments.

Arcturus: So, what's the plan, sir?

Shadow: You two will be on standby and help people evacuate the area. I'll help the pros take down the monsters.

Izuku: Wait, you mean arrest them, right?

Shadow: If possible. If not, then I'll handle it.

Neither of them acknowledge it, but knew he was more than likely referring to killing. They soon arrive to one of the sights of the explosions, and saw multiple Nomu there with pros fighting them.

Arcturus: (shocked) Christ all mighty, there's more of them.

Shadow: Guess I'm going into overtime.

Suddenly, he disappears in a flash of blue and reappears above one of the Nomu, delivering a roundhouse kick to the head. He disappears again and reappears above another one and smacks both his fists down on its head. Shadow does this again and does a spinning back fist to the head, knocking the target down. He finally appears on the ground and charges up his hand.

Shadow: CHAOS SPEAR!!!

With a flick of the hand, a few spears made of yellow-orange lightning fire and completely obliterate a couple Nomu.

Izuku: Whoa...

Arcturus: Amazing... (remembers their first fight) During that fight... He wasn't disappearing at all, but teleporting... (looks at his hands) Could I maybe do that...?

Pro Hero: You two get out of here! You're in the way!

More Nomu appear and the pros were working hard to fight them and the fires. One of them, Manual, was berating himself about something.

Manual: Damnit, Tenya! Where did you run off to?! I just hope you didn't get into any short of trouble.

Now that brought the attention to the boys. They knew Iida wouldn't run off like this, especially without telling his instructor where he was going. Then, the gears in their heads begin turning and their eyes soon widen at what this might mean. Both of them then take off running.

Izuku: Arc, you thinking what I'm thinking?

Arcturus: Yeah. Iida went after the Hero Killer on his own. That's why he interned at Hosu in the first place. Damnit! I should've gotten him to talk more, try to get him not to try anything stupid!  

Izuku: I know what you mean. But we can play the blame game later. We need to find him before it's too late!

(with Shigaraki and Kurogiri) 

At a rooftop far away from the battle, Shigaraki and Kurogiri were watching the chaos ensue.  

Shigaraki: The Nomu make such great playthings.

Kurogiri: Are you not going to participate in the fight?

Shigaraki: (grabs his shoulder) Don't be stupid. I'm still injured. That's why I brought those pets with us. (laughs) Once this night is over, the world will have forgotten you ever existed, Hero Killer.

???: You should not underestimate the influence Stain holds on the human mind.

The two turn around and see someone floating down to them.

???: People such as him always leave behind some influence.

Shigaraki: What the hell are you doing here?

???: Calm yourself, boy. I'm not here to interfere with your work. I have business of my own to conduct.

Kurogiri: We're honored you're here. Does this mean you're—  

???: I care not for your little "League of Villains" nor for Stain. Make no mistake, I do not support these so called heroes or accept the way this society in this. This world must be fixed, and I have the means of repairing it.

(with Y/N) 

Once the trio of villains set out the Nomu's on the City of Hosu, Y/N ditched the two and went off on his own into the city to see the chaos and panic unfold. Using dragon wings, Y/N flew high above the city and saw the Nomu's causing havoc. 

He didn't have as much enjoyment as Shigaraki, but he did have some enjoyment seeing some of the so called heroes try to figure out what's going on.

Y/N perched down on a ledge that was above an alley to take some time to himself and was about to move again until he heard what sounded like fighting. Looking down below him, he saw a sight of behold.

Y/N: Talk about interesting...

Below Y/N, was the Hero Killer Stain, battling against one of the members of the Iida family, Endeavor's son, the Ghost Rider, and much to Y/N's surprise, Izuku and Arc. He stuck to the shadows as he watched the fight from above, not daring to intervene to help Stain.

Sambamhaw: If you want to know how the battle will begin, it starts like this. (snaps his fingers) 

Back with the boys, they were running while checking around the area.

Lightning: Okay, Deku, you know more stuff like this more than me, so if you were a serial killer o heroes, where would you go?

Deku: Huh?

Lightning: What?

Deku: You called me Deku.

Lightning: That's your hero name, right? We should practice calling our codenames when we go on stuff like this. Anyway, back to my question.

Deku: I remember seeing the reports about the killings. Each of them happened in dark and secluded places with little to no witnesses. Which means they must be somewhere in the back alleyway.

With that in mind, they ran faster towards where they believe the place could be. Thankfully by miracle, they saw a man matching Stain's description, and both fortunately and unfortunately, Iida was there as well. Not giving another thought, the pair rush in and punch Stain away from Iida.

Lightning: Your hunch was right.

The villain skids back but still stands his ground.

Iida: Midoriya? Farron?

Deku: Don't worry, Iida. We're gonna save you.

Iida: You found him, too? But how?

Deku: I saw it on TV. With the stats on the Hero Killer, most of the victims were found in places where there weren't many people. So, in order to find you, we needed to search far away from the panic. In the back alleys of Hosu City.

Lightning: Can you stand up? We need to get out of here and call for backup.

Iida: Ugh. I can't move my body.

Deku: Huh?

Iida: It must be his quirk. Since he cut me, I've been paralyzed.

Lightning: That's the kind of quirk people speculated he might have. So drawing blood activates his power, huh? They then notice another pro not too far away.

Iida: Farron, Midoriya, please! Don't get involved. This doesn't have anything to do with you!

Deku: Iida, what are you saying?

Lightning: Nothing to do with us?

Stain: You both showed up to save your friend's life. You even made a big entrance. But I have a duty to kill him and this so-called pro. When your friend chose to fight me, it guaranteed that the weaker of us would be culled. So what will you do?

Admittedly, the boys couldn't help but feel intimidated by the man's face as he stares down on them. The look in his eyes weren't the same as the villains they fought before, but rather the ones of a fanatic. Thinking quickly, Arc rapidly sends their location in a group chat with the classmates.

Arcturus: (thoughts) Even though it was a guess, we should've told Shadow or a pro what was going on. So for now, the best we can do is hold him off until backup arrives.

Iida: Listen to me! Stand down. Run away. I told you, this has nothing to do with you.

Deku: If you really believe that, then why are you trying to become a hero in the first place?!  

Lightning: There's a lot of stuff we need to talk about once this is over, but that's not important right now. All Might was right about something he told us.

The two get in stances ready to fight.

Lightning and Deku: Meddling when you don't need to is the essence of being a hero!

Stain was surprised by those words before having a grin.

Stain: Heh.

Charging up in blue and green electricity, the boys rush in to fight. Since Arc was faster, he dodges over Stain and moves the pro away from the fight while Deku dodges from a sword strike and goes to land an over head strike.

Deku: A five percent... DETROIT... SMASH!!

He lands the strike on the head and hops back.

Izuku: (thoughts:)Full Cowling worked! I can still fight!

However, Stain has a grin and brings his sword up to his mouth. He licks the blade, and Izuku suddenly felt like his whole body was stuck.

Lightning: Deku, what's wrong?

He gasps as he realized what happened when he saw a small cut on Izuku's arm.

Arcturus: (thoughts) He's been paralyzed, and just from having a scratch? (notices the blood on the blade) It's the blood.

Stain: (to Izuku) You're not powerful enough. It's not that you predicted my movements. You just left my field of vision, and maneuvered so that you'd be able to get in a clean shot. But I saw through your plan. There are countless false heroes around here who are all talk, but I think you're worthy of staying alive. You're different from the others.

Lightning: Tell me, Stain. Why is that? What makes us different.

Stain: Those false heroes don't become heroes for the sake of it. All they care for is the fame, the money, and tarnish the image of True Heroes. They're corrupt and arrogant, and must be purged from those who are worthy. And then there's you...

Lightning: Me?

All the sudden, Arc dodges from multiple stabs coming in as he tries to throw in some hits to bring him down. However, he wasn't going down.

Arcturus: (thoughts:)He's fast, I'll give him that. Not to mention he's refusing to stay down. (looks around the area) I could try to throw a super sonic punch, but there isn't a clear and straight path I could take. Too many turns would decrease the speed and impact of it. But if I phase...

Arc then begins to vibrate his body to try and phase while dodging.

Arcturus: (thoughts) Come on... Feel the air around me, let my molecules feel the excitement, concentrate!

It didn't work as Stain suddenly impaled Arc's right arm into the wall with multiple blades. Just as Arc goes to grab them, Stain licks the blood and Arc was frozen.

Deku: Lightning, no!

Iida: Farron!

Stain then reaches out to grab Arc's mask, but he doesn't remove it and instead stare right into his eyes, like he's looking into his soul.

Stain: There's chaos inside you. You have what it takes to be a hero like Deku. However, looking into your eyes I see something else. It's not as a pretender or even a villain. You're in a state of limbo, bringing discord in your mind. You're gonna have to decide what path you must take before I decide to kill you or not. Until then, I'll let you live.

He pulls back and approaches Iida while his blade high.

Deku: Wait, no. Stop it!

He ignores him and raises the blade. Iida looked terrified at what could happen and the boys were now desperately trying to move but couldn't.

Lightning and Deku: Get away!

Suddenly, the sound of a car engine roars and fire shoots out, making Stain jump away.

Stain: Someone else to get in my way. Today's been full of distractions.

The car stops and they see a dodge charger with fire on the wheels at the hall entrance and two boys exiting the car. They were Shoto and Robbie, now wearing new costumes, and having their flames activated.

Shoto: Arc, you need to give more information next time. We were almost too late to stop this guy.

Iida: You too, Todoroki? Reyes?

Izuku: How'd you get here? Hold on, you're using your left side?

Ghost Rider: I was passing by when I got your message. I wanted to check it out and I was passing by Todoroki so I picked him up and take him with me.

Shoto: Next time, try to send something more than just your specific location. But you're not really one to send cryptic messages without a reason, are you?

Todoroki then uses his ice to get the paralyzed heroes away.

Shoto: So we figured you were in trouble and asking for help.

Ghost Rider: The pros are on their way here. You guys rest, we'll take care of this.

They fire their flames and chains, making Stain dodge them.

Stain: The skeleton... I must admit, it's an honor of meeting someone who understands my ideals, Ghost Rider. Even if you're not like your predecessor, you desire vengeance on this corrupt society.

Ghost Rider: (points to Stain) Chizome Akaguro... Guilty!

Shoto: You're just as they said you were. But you won't be taking any more lives, Hero Killer. 

Lightning: Shoto, Ghost Rider, don't let him get your blood. He's probably able to control our actions by tasting it. That's how he paralyzes his victims.

Shoto: He ingests blood to keep people from moving. That explains the blades. All I've gotta do is keep my distance.

Not after saying that, a knife goes in and grazes his cheek.

Stain: You have good friends, Ingenium. Or you did!

Ghost Rider stops him by hitting him with a fire-covered fist that sends him back. Stain then cuts on Robbie, but didn't see any blood and the blade melts.

Ghost Rider: Na-uh-uh. No blood to taste when you're a flaming skeleton.

Stain: How annoying.

Shoto and Robbie then throw ice and fire attacks at him while Iida watches, still wondering why they're going this far.

Iida: Why are you doing this? His fight is with me! I inherited my brother's name. I'm the one that should stop him. The Hero Killer is mine!

Shoto: You're Ingenium now? 

Strange. The Ingenium I knew before never had that look on his face. You've got a dark side. Guess my family's not the only one.

Ghost Rider: Leave the desire for vengeance to me. It's not a good look for a Boy Scout like you.

The ice then shattered and Stain was back in.

Stain: You blocked your field of vision against an opponent who's faster than you. Rookie mistake.

Ghost Rider: Block this!

He throws one of his chains up, wraps it around him, and drags him on the side of the building. At the same time, Arc and Izuku suddenly move again and landed a double punch on him.

Shoto: Midoriya! Arc!

Lightning: We're back at it again!

Shoto: So he has a time limit.

Pro Hero: No. Those two should've been the last ones to be free. I still can't move a muscle.

Ghost Rider: Is that so...

Stain recovers and breaks free. Todoroki shoots more ice, allowing Izuku and Arc to regroup with them.

Deku: He swallows a person's blood to freeze them, but Lightning and I were the ones freed first. I've got three different guesses why. His quirk could be less effective the more people he uses it on. The amount ingested could play into how long it works. Or there could even be a difference based on a person's blood type.

Stain narrows his look at them at the last one and Arc catches onto it.

Lightning: You're right on the third. We're O-type, which means the higher the blood, the less the effects last.

Stain: (smiles) So you figured it out. Bravo. How impressive.

Ghost Rider: Doesn't matter how his quirk works. All I need to do is look into his eyes.

The four stand as they wait for the next move. All the sudden, the sound of something was approaching them.

Deku: Is that a jet?

Lightning: Doesn't sound like one.

All the sudden, something lands directly across from them. Looking out into the street, everyone, including Stain, all look in shock at seeing a large robot standing before them.

Stain: Don't tell me that brat managed to actually get one of those.

Deku: (shocked) No way... Is that...?

Lightning: Yeah... A Sentinel.

Arcturus: (narrator) In the early years when quirks came into existence, many people didn't accept them. So much so, secret societies created weapons of mass destruction to kill people with quirks. This was one of those weapons. The Sentinels were built to locate and destroy quirk users by any means necessary, but it wasn't until more people gained quirks did the project shut down. Still, some remnants of the past come back to haunt the future. That night, we would be lucky enough to not only survive the Hero Killer, but the ultimate quirk destroyer.

Sentinel: QUIRKS DETECTED. TERMINATE ON SIGHT.

Chapter 8 ended. 

I hope you guys enjoy this chapter. Especially with the students fighting the Hero Killer Stain. 

Speaking of which, how and when do you think Arc, Wanda, Izuku, and Hitomi will manage to get Y/N back? I know it will mostly involve fighting and emotional moments with that part. 

Don't get me wrong, we're still a villain in terms of what Katsuki dead and achieving our goal. But deep down, I felt bad for those four, including Momo, Kyoka, and Mina who are also his friends. 

If I had a few ideas for that part will be either at Izuku vs Katsuki during the end of Season 3 with Arc and Wanda or something similar. 

It'll be like Y/N's an Anti-hero/villain thing, you get what I mean. Anyway, let me know what you guys think at the comments below. Peace out and enjoy!