Tony Stark stood in his Quinjet's supply area. He looked at his ace weapons. They were made in case Maximoff ever went rogue. He called them the Iron Chains. They were made using the material known as Nanominium. It took a very costly deal with the MI13 to secure a supply chain of this metal. This metal was special for the fact it possesses anti-magical properties, and from what he has learned by having Cho secretly experiment on Maximoff's blood under the guise of helping with healing, is that her powers are magical as the energy signatures are similar to the MI13's data on magical energy. Tony had to admit, at first, he didn't believe it was magic but soon relented. The deal was easy to make as soon as Tony told the MI13 about who Wanda was, how she got her powers, and how she was an actual Nazi before Steve Rogers hid her crimes and made sure everyone stayed quiet. The MI13 declared Wanda dangerous and agreed to supply Nanominium; in return, Wanda will be shipped to them to be contained. Tony agreed that way, even if Steve somehow won, he would never get her out. Tony agreed after learning about the Scarlet Witch prophecy; she needed to be contained or killed if too dangerous, but Steve Rogers would never allow that, so he can't know where she is. The MI13 is stationed there to take her in; they were posing as the accords agents.
Tony grabbed the weapon he made; it was called nano spheres. There were part of his experimental nanotech, like his Mark 47 Iron Man suit, but unlike the suit which was so big, he had to work on stabilizing the suit and making so the metal doesn't lose durability when forming from one shape to another. These spheres had one set shape to turn into a cage to trap Wanda Maximoff. Although Magic proof, he couldn't be sure, so he had shockers just in case. He couldn't have the Scarlet Witch get out before she was contained. Due to how small the structure is, it also made it so the nano spheres, when turned to cages, never lost strength or durability.
Tony, after hearing the Scarlet Witch prophecy, had one aim, and that was to kill or contain the lunatic known as Wanda Maximoff before she can take over or destroy the multiverse. It was one life for a googolplex, and Tony held no love for the one life; she ruined the Avengers. If she wasn't alive, Ultron would have never happened, the Accords would have never come to fruition, and Rogers wouldn't be fighting against the will of the people. The people who he claims to fight for, the little guys, want them to be accountable. How could Steve deny them? Sure, the accords right now aren't perfect, but they can be fixed, like how women legally couldn't vote; that was fixed. No laws were perfect at the start; does Rogers live in a world of sunshine and rainbows? God, he couldn't be that dense.
Tony suited up in a special version of the Mark 47 Iron Man suit made out of Nanominium; it itself was as durable as Vibranium, according to the MI13, which meant Rogers shouldn't stand a chance; his only chance of breaking the suit was the shield, but with this, his advantages are neutralized. Tony, honestly, after the confrontation with Rogers back in Bucharest, was getting sick and tired of the self-righteous Hydra-defending bastard. If Rogers doesn't give up, Tony may not hold back. Tony can feel it, years of jealousy and resentment he has towards Rogers due to Howard, years of anger he has built up after meeting Rogers. He won't be able to contain it. Tony knew one thing: if it came down to it, only one of them is walking away in good condition.
"Stark, we are here," Natasha said.
"Fine, let's get this show on the road, Romanoff." Tony said as he walked with her and Rhodey to the airport. They had the airport evacuated. Tony had not told them about his plan and the deal with the MI13; he knew Rhodes would agree. But Romanoff, she was a liability. She was one hand on, which meant she was not fully aboard.
Tony and Rhodey landed before Cap after they shot the helicopter he was running to. "Wow, it's so weird how you run into people at the airport. Don't you think that's weird?" Tony says sarcastically.
"Definitely weird," Rhodey replies.
"Hear me out, Tony. That doctor, the psychiatrist, he's behind all of this," Steve says as he says that T'Challa jumps over a truck.
"Captain," he scowls.
"Your highness," Steve replies.
"Anyway, Ross gave me 36 hours to bring you in. That was 24 hours ago. Can you help a brother out?" Tony says.
"You're after the wrong guy," Steve says.
"Your judgment is askew. Your old war buddy killed innocent people yesterday," Tony says as he zones out until he had enough.
"All right, I've run out of patience. Underoos!" Tony says as Peter shoots a web, stealing Steve's shield and binding his hands.
"Nice job, kid," Tony says after a bit. Tony decides it's time to attack; Rogers was not going to listen. "Oh, great. Alright, there's two on the parking deck. One of them's Maximoff, I'm gonna grab her. Rhodey, you want to take Cap?" Tony says as he flies towards Wanda.
"You should have stayed home, Maximoff. You're in big trouble," Tony says as Wanda's eyes glow. He had enough. He aims a Nanosphere at her.
"You locked me in my room," Wanda says, and before she can do anything, the spheres launch towards her. She tries to use telekinesis to move it, but it fails and penetrates through her magic and taps her body as cages form around her.
"No, this is me locking you up," Tony says as she screams.
"Let me out, let me out," Wanda screamed.
"What have you done to her? You monster. Release her now," Clint yells, running towards and tries to break the cages, but they are too strong. Tony zooms down, grabbing him by the neck.
"You know, you were always cocky. You think you're important. But newsflash, you're trash. You have no powers, no suit; you're a liability," Tony says as he throws Clint away into a trash can and then flies towards and with a single punch knocks him out cold.
"Friday, contact the MI13, tell them Wanda's been secured, and if she shows signs of breaking out, shock her, but not too much, only enough to pacify her," Tony says and flies around.
"Got it, boss," Friday replies.
Tony then proceeds to assist Spiderman in taking out Sam as Barnes and Rogers run towards the Quinjet hangar. Tony lasers the foundations, making it collapse on Bucky, who was ahead of Steve, killing him.
"NO," Steve runs towards Tony and tries to punch him. But the Nanominium is too strong, and Steve is left punching air.
"You monster," Steve says.
"No. He was a criminal. He
attacked the king of Wakanda, and he killed innocent people, and you defend him," Tony says as he punches Steve back, shattering Steve's left arm, which he used to block the attack.
"You're no better than them," Steve says.
"Say the one that advocates for Hydra, but then again, I shouldn't be surprised after all Red Skull had to have gotten his super serum from someone, and the only person who could have given it was Abraham Erskine, the same man who gave you the serum. He managed to trick my father, Howard Stark, to help him help you, but I'm no fool," Tony said as Steve got enraged and started swinging like a wild gorilla. Only for his punches to do nothing. Tony smirked and kneed him in the balls.
"Oof, guess I spared the world from Rogers Jr.," Tony mocks and proceeds to punch Steve's chest and stomach. Steve screamed out in pain.
"This is for taking Howard's attention," Tony yelled, punching him in the face, enjoying the crack he heard when his fist collided with Rogers' skull.
"This is for the loveless nights my mother had to endure because you ensnared Howard," Tony yells, kicking him on the side of his stomach as another crack is heard, and Steve drops to the ground.
"And this is for all the stress you gave me, all the times you looked down upon me since the Avengers was formed," Tony yells as he stomps on Rogers. Tony then proceeds to aim his repulsors at Steve Rogers, but then Rhodey in War Machine armour comes from behind and tackles Tony.
"I can't let you do this," Rhodey says.
"Rhodey, get out of here. This has to happen," Tony Stark says as he struggles against Rhodey, who's restraining him.
"Look, Tones, I know Rogers is the cause of your suffering, both childhood and adulthood, but we need to bring him in. Plus, he's already down, and you killed his best friend; let him suffer like you did," Rhodey says, knowing that will calm Tony down, and he is right.
"Fine. Contact Ross, have him collect the traitors to humanity. And don't worry about Wanda; some people have already taken her," Tony says, knowing that Wanda is most likely with the MI13, who will keep her in check, and if needed, kill her.
"Will do," Rhodey says.
A few years later, Wanda struggled against the cages. "Let me out. Let me out," she yelled. She couldn't even channel her power, and if she punched the cages too much, it would give her a light shock, enough to pacify her but not kill her. She hated Tony Stark for what he had done. She hated how he stole her freedom, and she swore once she got out, she would kill him. She would make him suffer for what he had done to her.
"Ms. Maximoff, I am Pete Wisdom of the MI13, and you have been declared too dangerous to live. You see, you are a supernatural threat to this world. Your destiny is to either destroy the multiverse or become a dictator that rules it," Pete says as he waits for her to take everything in. "It is for that reason you will die today," He says, aiming his gun and pulling the trigger, and with that, The Scarlet Witch's life came to an end, and the multiverse had been saved.
Bonus scene:
Meanwhile, on the raft, Steve Rogers screamed as Thaddeus Ross cut him open. "You know, the funny thing is this is all legal. Any enhanced that are 18 and over and do not sign the accords are not registered as Superhuman and therefore have no rights. Stark's trying to change that, but after the civil war, he has no support. The public wants rebels like you gone. Thank you very much for assisting my anti-enhanced campaign; I knew by presenting the accords, you would be against the one document that could be used to help and keep enhanced safe. I'm pissed Stark used all his pressure to protect minor enhanced, but we can't have them all, plus having the original super soldier here is good," Ross said as he nodded to his scientist, who proceeded to inject him with chemicals to damage his organs, all to see how fast they regenerate and what his body does to heal like this so they can replicate it.
Ross laughed as he heard Rogers' screams.