"Good becomes great; bad becomes worse." The reason why Steve was chosen, but Steve's not sure if he should believe it anymore. Why? Because he's been turning red a lot lately. It started when Steve lied to Tony about what the funding was really for. It wasn't to hunt down Hydra or for the Avengers. It was to use the money to find the funder's parents' killer. Steve also became red whenever he thought of Tony, because he never saw Tony as human or a teammate, but as a bank giving free money. Natasha encouraged it, so he thought it was good, but the serum showed it wasn't. Did Steve care? No, because his ego made him think he was good, so him becoming red was great.
The second time he became fully red, other than little bursts like when he lied, had bad thoughts, or basically did anything considered bad or a sin, was when he trusted Maximoff. His body became red, signaling that he was wrong and that those brats were nothing but Hydra scum. But Steve ignored this; he needed to use them to set up for Bucky. After all, if he could save two willing Hydra twins and convert them to good, then he could surely bring Bucky back to the good side, and Tony wouldn't have anything to argue about when he found out about Howard and whatever his wife's name was murder at Bucky’s hands.
The third time he became red, it almost stuck, because he almost killed Tony who was innocently working with Bruce to give Jarvis a body. Steve knew Jarvis was good; he had worked with him. But Steve, wanting to protect Bucky, felt that he could get rid of the Stark threat to Bucky’s life and play it off as a hero. Unluckily, Stark survived, and like other times, his red skin went back to normal. Although it did flicker when he defended to Bruce why he had to work with the person who mind-raped him. Natasha was a big help. Bruce didn't know this, but Natasha and he were actually involved while she was in a relationship with him. She was using Bruce to control Hulk; after all, why would she want Bruce when she could have him, the perfect product of Super Serum? The perfect human. As he thought this, he flickered between having red skin and his usual white.
The fourth time his skin flickered red was when he lied for the Hydra girl, Wanda, to have her join the team after Ultron was created. He guilted Tony to leave while lying that he would miss him. He also lied to Thor so that he would approve. Thor didn't approve; he just left, wanting nothing to do with the girl who was granted powers when the mind stone was corrupted. He believed her to be Ultron's mother after his vision cleared Tony.
The fifth time he became red was when Steve lied that he was against the Accords because they were unfair and had too much red tape. He opposed them because there wouldn't be any way he could search for Bucky without permission. Even if the Accords were fair, he would have opposed them and convinced the team to do the same. Well, it didn't really work; he only managed to convince the people with low IQ in the avengers But what hurt him more was that his pet slut Natasha joined Tony. How dare she oppose Steve, her owner? He would punish her. He owned everyone on the team, even Tony. He was better than them. He was Dr. Erskine's perfect super soldier. To think these idiots would follow Tony, a narcissistic, selfish bastard. It pissed Steve Rogers off, because he enjoyed having Natasha; it allowed him to feel like Bucky, having the most beautiful woman, in his opinion, after Pepper. She was nicely dressed and wasn't a slut like Natasha, but that woman was into Tony. So she obviously had some screw loose or something. She was even better than Peggy she actually acted like a woman people of his time would respect. The only problem was Tony corrupting her to be a CEO. Everyone knows a woman can not be a CEO they should be at home cooking food and taking care of children is what Steve believed. This was further proven by the hateful looks of disgust she gave Steve every time he entered.
The next time he turned red was when he watched Rhodey be hit by Vision, allowing him and Bucky to escape. He had to sacrifice a few pawns, but oh well, at least he and Bucky were safe; that's all that mattered. It was at this point that someone noticed.
"Stevie, you're turning a bit red. Are you okay?" Bucky asked, concerned but with suspicion. Steve quickly thought back to his time with Bucky, and he turned back to normal. He had managed to control his little shifts.
"I'm okay, Buck. Just a bit stressed and worried about my team," Steve said, flickering red briefly since he lied.
"Okay," Bucky replied with suspicion in his tone. Steve, being Steve, believed he had Bucky wrapped around his finger, just like back in the days when he would pick fights and play victim, having Bucky, the strongest kid in class, beat up those who opposed him, claiming they were bullying him. He smirked, not noticing Bucky's suspicion.
Steve had been turning red a lot lately, which reminded him of something Dr. Erskine had warned him to watch out for. But maybe it was just stress, after all, he turned back to normal. If Steve were to completely turn red, he would do whatever it takes to defend the world. He wouldn't let a Red Skull 2.0 rise. Even kill Steve.
They arrived in Siberia, and that was when the final shift happened. As soon as he lied to Tony about everything, he didn't know it was Bucky, which also silently included the fact that he used the funds to find Tony's parent's killer. He saw Tony as a bank of free money to save Bucky. He finally gave up playing the hero and admitted to knowing and silently admitted he using Tony to save Bucky. His body turned red, and he shifted. He looked into the black reflection of the screen Zemo used to show the Stark parent's murder. He had fully become Red Skull. He tried to shift back, but he couldn't. He saw an angry Tony and Bucky with looks of disgust.
“Steve, bad becomes worse. What happened to my friend? What happened to you that you would become an exact copy of Red Skull?” Bucky yelled.
“I'm nothing like Red Skull, I'm better. He was an idiot, ugly, declaring world conquest. Me, on the other hand, I played ally with Tony to use him to get you. And now that I have you, I won't let you go,” Steve said as he started to say the trigger words, but before he could finish, Bucky shot him.
Steve was dying, a look of utter betrayal on his face. “Bucky, why? We were meant to be together until the end of the line, remember,” Steve said painfully, blood spits seen as he talked.
“You crossed the line, Steve. You became something worse when you lied to your friends, used them, saw them as pawns, and when you tried to control me. Your outside now reflects your inside. You became the very thing you swore to destroy,” Bucky said, walking up to Tony before putting his hands up.
“I surrender. I don't want to fight anymore. Just kill or arrest me,” Bucky said. Steve tried to say something; luckily, his life ended, so Tony and Bucky didn't have to hear anything from Red Skull 2.0.
“I want to kill you so badly. Why don't you defend yourself?” Tony said, aiming his repulsor, wishing for a fight, a chance to beat down his parents' killer.
“Mr Stark,” a voice came from behind. “Let him go. It was Hydra. You can see it wasn't James Barnes. He even killed Steve Rogers his friend who was becoming Red Skull reincarnated.” They saw T'Challa saying this.
“Tell me, T'Challa, can you forgive your parent's murderer?” Tony asked.
“I won't kill them. I will take him to jail,” T'Challa said.
“Fine. I will take Barnes to jail as well,” Tony said.
“Mr. Stark, it wasn't…” T'Challa was cut off.
“No, if that's what my victim has decided, then so be it. If you want to repay me, please help Mr. Stark's teammate in the black armor, War Machine, and provide me with lawyers so that I can legally be cleared and not have to be on the run. I'm tired of fighting and running,” Bucky said.
“Fine,” T'Challa said.
A few years later, Bucky had his trial and was released after serving time for murdering the Accords people. He was cleared of charges as the Winter Soldier but opted to do community service to ease his soul and punish himself for not being strong enough to resist mind control. Steve's team was prosecuted. Wanda found herself dead at the hands of Tony in Sokovia. The Sokovia government learned the truth of Ultron and wanted to make a statement by reintroducing Salem trials, having Tony be the one to burn, putting an end to her entire disgusting Hydra bloodline. Natasha and Clint were sent to jail but was murdered by SHIELD agents who had infiltrated the prison wanting revenge for the data dump. Scott Lang and Sam Wilson were sentenced to 10 to 12 years.
Hank Pym went broke having to cover damages done in Lagos and places the rogues went because his suit was used. He also had to pay a hefty sum to Tony for defamation and spreading lies that apparently Stark stole from him, which Scott said, and since Hank did not correct that and Tony wasn't born at the time the particles were stolen, Hank lost the case and owed Tony millions, if not billions.
Right now, however, they were standing over Thanos' dead body. Tony had used the wound made by Thor's Axe Storm on Thanos to send nanoparticles in and expand, destroying Thanos from the inside. Bucky stood as the new captain america in time Tony had forgiven him. Tony was thankful to T’challa who stopped him from killing Barnes. Now Bucky was Morgan Starks Uncle Bucky and he swore to protector and not let her become like Steve Rogers.