Tony's face fell, his mouth agape and ready to retort with equal destruction that you had just stabbed into his chest, but he couldn't do it. The words seeped into the recesses of his mind, eating away at his thoughts, destroying his sanity neuron by neuron. You had planted a seed of doubt, and a seed of hatred that would, unbeknownst to you then, escalate to such a fevered state that the nuclear explosion yet to come would be obliterating.

"I didn't know you thought that way about me," he whispered, his voice shaking. "I wish you would have told me sooner."

"Tony...that didn't come out the way I meant it to...I'm sorry-"

"Yeah, me too," he nodded with a sad smile, before turning away to leave. His watch sounded with an alert, followed by an image that brightened the hallway around you; you would normally take a stand at his side to see what information was coming in, but you held firm as if you had just been informally released from duty. "What am I looking at, FRIDAY?'

As Tony's voice continued while he walked, T'Challa again appeared to stand with you, looking out over the grounds in much the same was as Tony had been. The man was an enigma that you couldn't read, and with each sound of his voice, you had no idea what words it would carry. "Is it over?"

"Is what over?"

"Your engagement."

You turned to the man with a gasp, unable to contain your shock. "I don't think that's any of your business. I couldn't care less what kind of arrangement that you and Tony have, but it definitely doesn't give you any right to ask about our personal lives."

"Hmm, perhaps that is true, I apologize for any insensitivity. However, your personal life does have some bearing on my next actions. You must come with me." T'Challa reached out for you again, but this time you evaded his grip, inciting the quietest growl of offense from his throat. He paused and lowered his hand, closing his eyes for a second and taking a long, deep breath to calm his reaction to how resistant you were being. It wasn't something that he was accustomed to in his role as Prince, and now as King. "(Y/N), I would appreciate your assistance. If you would please join me?"

"Assistance with what?"

"You know where he is."

"And you think that I'm going to tell you?" you laughed. "Well, I'm sorry to be such a disappointment again, but I have no idea where they went. He's closed his mind to me and won't connect. "

"But that doesn't ensure that he will not do so again."

"Fire up the chopper," Tony said from the other end of the hallway, turning quickly to make his way to the hangar. He didn't even so much as look at you, making it unquestionably clear that you weren't invited. T'Challa had heard as well, with just a hasty look over his shoulder being enough to determine his next course of action.

"Come with me," he ordered much more firmly and succeeding in taking your arm, "this is not finished. You may not know where I can find Barnes, but if Stark knows, you're my best guarantee to find out."

And find out, he did.

~~~

"I know that road. What is this?"

As Tony watched a screen that you couldn't see from the vantage point where T'Challa had held you back, what you could see was a wave of pain slowly crossing his features. You could barely make out what he was looking at, but it was tearing away at him like nothing you had ever seen in him before; even the look on his face at the compound only hours before was nothing in comparison to this destruction. Then, one word, called out in pure, blood-chilling terror, had you breaking free from the King's grip to hurry to Tony's side; you took his gauntlet-covered hand, and he never tried to deny you.

Howard!

"Tony," you gasped as you watched, as your mind caught up to what you were seeing, "turn it off."

As his mother's voice was silenced, as he watched with a building rage, his grip on your hand nearly crushed the bones within it, but you didn't falter. Bucky's features lit up the screen, and your heart stopped. "Buck?"

"Did you know?"

It wasn't immediately clear who he was asking the loaded question to, but you turned to see him staring at you with a desperate hope in his eyes that you would give him the only answer his heart could withstand. "No, Tony, I didn't, I had no idea."

He then turned to Steve, to receive a single word from the man who was supposed to be his friend. A man that he had hated for so much of his life, and he had no urge to return to those feelings after all this time. But even as he waited, Tony knew what Steve would say.

"Yes."

"Tony-" you tried, but all it got you was a hard shove of his covered hand against your chest, not to push you away out of anger, but to protect you from what he was about to do. Your body bounced against the rough wall, dropping you to the floor with a wince of pain at the impact, while his other hand struck down Steve and set the most destructive fight you had ever seen into motion.

"We must go," T'Challa urged, taking long strides towards you from where he had watched the scene play out. "We cannot let that man escape."

"I have to stop this..." you whimpered, your body arguing with every movement. Your reaction was visceral, making you sick at the sight of what was happening just beyond your reach. A man you loved with the core of your being, a man who had come to be one of your best friends, and a man you were forever bonded to were on a path to destroying each other, and you were powerless to veer them from it.

"You will be killed if you try. Come with me now, (Y/N)."

"No, I won't." Pushing yourself up and onto uncertain legs, your head spun at the shift in position; you reached back at the sensation of a trickle against your scalp, only to find that the hit against the wall was harder than you thought. "Even if I can't stop them...I can't leave them."

"(Y/N), please listen to me, and hear me when I say that you will provide no benefit to them if you stay. This fight has many contentions, and you are one of them." T'Challa turned at the sound of the heavy, rusted door opening again, and he could wait no longer. "I cannot stay and argue this with you. Just don't get yourself killed," he hissed, turning to give chase to the man at the center of his own vengeance.

You knew that you had no chance to stop any of them by physical means, and you had no idea if anything you had to say would be heard through their rage towards each other. Bucky was doing his best to stay one step, or one level ahead of Tony, with Steve following to try to slow him down to give Bucky the smallest chance of getting away. FRIDAY was doing all she could to keep the suit in the air, it's boot jets failing and sputtering just enough to keep him from free-falling to the base of the bunker. In the end, none of her efforts mattered when Steve's grappling hook dug into the suit's armor, wrapping around its neck to drag Tony into whatever hell waited at the bottom of the cavern.

~~~

But Steve had miscalculated; he thought that bringing Tony to the lowest point would allow Bucky to climb his way out. What had happened was a poor tactical move, giving Tony the high ground over him, staring down through the mask with a fury that didn't need it to be lifted away to be felt. "This isn't going to change what happened."

"I don't care. He killed my mom," Tony answered, his voice as broken as his heart had become. Yours began to shatter with his at the sound, and when his attentions turned to you, watching and waiting for you to climb down and drop onto your feet next to him, you were quickly, utterly destroyed. But you wouldn't let him see that; he was suffering enough and you refused to entertain making it worse. Never again. "What about you, sweetheart? You're the soulmate of the man who killed my parents. What kind of person does that make you?"

"A person who will always choose you."

"Okay," he sighed softly, and you could hear his attempt at a smile within it, right up until the second he turned and threw himself at Steve as if time hadn't just stopped for the two of you. He ignored the chance that this could be turned around, and threw his pain into the battle with a new purpose, and a new, unbridled wrath.

You watched from where you had thought you would be safe, just back from the ledge that Tony had just leapt from, but for Bucky, it wasn't far enough away. He took a few bounding steps past you, his arm connecting as he passed, pushing you back and away to where he hoped that you wouldn't see who he was about to become. He flung himself at Tony, without a care to himself, working seamlessly with Steve to keep him occupied. Tony looked as if he was outnumbered and outmatched, and when he was literally backed into the wall with nowhere to go, he found his only way out; through Bucky.

"Buck!" you called out to him as he fell to his knees, staring at the gaping absence of his left arm. It was gruesome and abhorrent to see what Tony was capable of, and you tried your best to rationalize it away as self-defense just to soothe your own conscience. As Steve picked up the fight and led Tony away, you jumped down to see the damage for yourself, cradling Bucky's head on your lap to calm him. "Hey, you're gonna be okay. I'm right here."

"But...you just said...you choose him..."

"Shhh, quiet. That doesn't mean that I can't help you. That doesn't mean that I'm going to let this continue any longer, either. This has to stop before they kill each other."

"(Y/N), don't go...stay by me..."

"It's okay, Buck, I'll be fine. I'm mostly sure that they won't hurt me on purpose," you tried and failed at reassuring either of you. Holding his head in your hands, you gently rested it on the cold ground, stood and turned towards the two men, waiting for your opportunity to take that leap of faith either into a peaceful resolution, or into a flaming end of everything that you loved.

Either way, the only thing that you could see, and the only thing that drove you towards an insane move that was sure to fail, was that Steve was about to slam his shield into Tony's face. He was going to kill him, and in that moment, anyone could have mistaken you for a super soldier as your adrenalized strength took over. You burst forward, turning to square your shoulder for the hit, knowing that you were likely to shatter it on impact, but not slowing at all. You were moving so fast, in fact, that even as the shield crashed into the arc reactor and not Tony's face at all, it was too late to stop. You caught Steve in the side before he brought his arms down, knocking the wind out of him as you both tumbled to the ground, and feeling the bones of your shoulder separate and crack first from the hit to his rock-solid chest, then to the frozen concrete beneath you both.

"(Y/N)!" Tony called to you first, but he was unable to move after the jolt to the suit. "FRIDAY, is she okay?"

"I'm reading a broken right shoulder, splintered clavicle, compound fracture of the humerus, and a mild concussion, boss. The concussion appears to have happened shortly before this incident."

"(Y/N), why did you do that? I only wanted to stop him," Steve joined in. He rolled over to face you, quickly finding his way to his knees to be at your side. He reached out to try to lift you from the cold before it set into your body, but his hands simply hovered and he looked terrified to try. "Tell me where-"

"Everywhere," you winced, barely able to breathe with the pain. Any little movement of your chest to expand for air shifted your shoulder, leaving you with a building agony as each second passed. "You were going to kill him, Steve. Don't touch me."

"I wouldn't-" he tried, his hands not moving away despite your tone.

"I said...don't touch me."

Bucky was next to try to come to your aid, but he was suffering enough on his own and he couldn't find the energy anymore; he wanted to help, it was driving him through instinct, but his body was fighting against it and only tiring him more. Steve had no choice but to run, once again, and for the foreseeable future ahead. The regret carried his frame as he pulled the shield from the reactor with an exhausted groan, his steps dragging as he struggled to help his friend from the floor.

"That shield doesn't belong to you," you spat in anger at the man you no longer knew. "You don't deserve it. Tony's father made that shield."

And just like a church bell that tolls for the memory of the lost at the close of a funeral, the shield rang out as it fell to the ground, leaving Steve's hand for the last time.