Natasha Romanov was a glacier. She was powerful and cold, and her wrath would seep into her enemies just by being in her presence. The cold fury that she was known for was a bolster to her reputation, even if it didn't work as people seemed to think. Almost everyone who knew her assumed that she was mostly either always angry or unfeeling, but the truth was she was just like a regular person in those regards. Well... mostly. Hot rage was explosive and burned its victims in a fiery rush, but cold fury was patient and almost impossible to melt. It was preserved until justice or revenge had been taken, which meant there was no mercy.

The only people who had ever seen Natasha Romanov's true rage and fury were dead. All except for Clint Barton. This was because her ice only ever made an appearance if it had to do with family. Always because she was avenging them. Until the day that she had managed to save Clint from a face from her past, and he had seen what she was capable of when she fought with a passion. True fury never formed if she was just doing her job. Oh, she could get angry, but the deeply personal tragedy required for producing ice couldn't be imitated. She needed a real reason, something that was capable of scarring her already mangled soul.

The betrayal of Steve Rogers was one such reason for Natasha's ice to come into play.

She had been fairly neutral in her stance of the war. While she agreed with the general idea of the Accords, Natasha's only real concern had been keeping her family together. She had believed that Steve had been a man good enough to call the shots for the world, but she knew that the world wouldn't - couldn't - stand for that, so that was why she had supported the Accords. Tony was right, they were going to happen either way, but by being a part of it they would be able to contribute to the process and make sure that it was fair for everyone involved. She had hoped to make Steve see reason, but at the airport - when she had realised that he wasn't going to stop fighting - she had let him go. She had realised that her family had fractured and her last gift to one of the members of it had been his freedom. It sucked, but Steve Rogers was a good man who was able to make the right calls, so the world would be fine.

That had been a mistake.

Her next mistake had been running. She knew that she couldn't stay after her actions at the airport - not without facing the wrath of Thunderbolt Ross and all the support he had drummed up. Besides, there had been nothing left for her there - not now that everyone was imprisoned or on the run. Natasha had left with a parting shot at Tony about ego because she was hurting and she had a strange series of feelings running through her chest that she just couldn't seem to identify. It took her four hours and nineteen minutes to realise that one of the prominent things she was feeling was guilt. That... That had stopped her in her tracks. That was when she finally looked at what she was doing.

She was doing what everyone else had been doing for years. She was ignoring the consequences of her actions and running away from her problems. She was leaving Tony behind to handle everything and face off the world on his own. She was leaving the man the Avengers had each betrayed, behind with the emotional turmoil, self hatred and misguided guilt that he would undoubtedly feel for Rhodey, for Vision, and for the Avengers as a whole. For what the Avengers did to the world and its people. She was leaving behind the remnants of her family.

Without even trying, Natasha knew that she would be unable to move another step that wasn't in the direction of the people she had left behind. The paralysed soldier, the synthetic human, and the self-made hero who would take on the universe even while he protected the world. These were the people who needed her there and then. These were people she couldn't run from. No matter what the possible consequences she would have to deal with, Natasha had to go back.

When she arrived at the compound, however, it was to find Vision talking to Pepper, who must have learned about Rhodey's fall and come as quickly as she could. Vison looked... broken. His immaculate posture was replaced by a hunched back and drooping shoulders. His usually expressionless face and soothing British tones were gone in exchange for a mess of guilt, distress and worry. Pepper was looking nervous - probably worrying about Rhodey and Tony, while also trying to deny her feelings for the latter - and her usually pristine business shirt had an easily noticeable coffee stain near the collar - something the CEO was probably aware of (it was Pepper after all), but unconcerned with in the face of all that had happened recently. Natasha couldn't blame her. A lot had happened in the last few days that even she was finding hard to believe.

She soon discovered that Tony had already gone after Steve and Barnes, but Vision also made sure to say that Tony was starting to suspect another party's involvement and that he wasn't certain whether Tony was going to apprehend the super soldiers or aid them against a possible new threat. Natasha wasn't sure about how that would turn out, considering that this was the first she had heard of another enemy (apart from Steve's righteous one liner at the airport, which hadn't made any sense at the time).

Her concerns were proven right when FRIDAY's voice interrupted Pepper's attempts to console Vision about everything Wanda did to him.

"I've just lost contact with Boss!" Her Irish accented voice was infused with panic that an AI made by anyone who wasn't Tony Stark would be incapable of.

Pepper and Natasha immediately straightened in concern, while Vision raised his head, a new worry visible as a new crease on his forehead.

"FRIDAY, what happened?" Pepper kept her cool, but Natasha could see her barely restraining the urge to get up and pace.

"Boss went to a Siberian HYDRA bunker to help Rogers and Barnes stop someone activating five of HYDRA's Winter Soldiers. They turned hostile and have disabled the suit. I... I'm afraid for his life."

"Give me the coordinates, FRIDAY. I'll be there to aid Mr Stark in a few hours." Vision said before phasing through the walls, leaving Natasha and Pepper to worry silently or frantically for the life of the man they both tried to deny they loved.

And when they saw the aftermath of whatever had happened in Siberia, Natasha became very aware of the cold of a Russian winter settling in her soul. She knew then that she would carry it with her until Rogers was frozen by her.

However long it took.

~0~0~0~0~0~

Clint Barton didn't sleep very well these days. Granted, he never really did - not with the things he'd seen in his life - but this was different. He was no stranger to guilt; it came with a past like his, but he had never felt it this keenly, except for once. After the battle of New York and the fact that he had killed his fellow agents had finally caught up with him, he hadn't been able to sleep for months. Natasha had done what she could to help, but the only person who might have had a chance was dead. He couldn't go to his wife and kids - not like he was then - but he knew staying with SHIELD was only going to worsen things - at least at the time. If it hadn't been for Tony and Banner... he didn't know what might have happened.

But anyway, it was the fact that he constantly felt the same as he did when he'd been trying to come to terms with the fact that he had killed his own people - his family - was enough to stop him sleeping again. It meant that he believed - that he knew - that he had been in the wrong. That he had made a grave mistake. That he'd betrayed his friend. Of all the things he ever regretted in his life, it was always the ones where he hurt people he cared about because of something that was actually his fault that burned the worst. The thing about Clint was that he didn't have a guilt complex (unlike certain genius billionaires or gamma ray scientists), which meant that when he regretted something, he generally had good reason to.

That was why he was currently in the kitchen at 3am, debating whether or not he should start drinking coffee, while trying not to examine his recent thoughts about his part in the Civil War. It was also why he was in a position to hear the sound of four fingers drum along the counter top once. Clint didn't turn around or even startle. To be honest, he'd been expecting something like this, but he hadn't been sure if he would still warrant a forewarning in Natasha's books. Clint knew from Steve that she had let him go at the airport, which meant that her still siding with Tony meant that she truly believed in what he was doing. It also meant that she was likely as pissed as everyone else they had encountered since they'd returned to the states.

Still facing the sink, Clint tapped his forefinger on the tap twice, the same as he'd used to do in his SHIELD days whenever either he or Nat needed to talk to the other. He didn't hear her move, but Clint knew that she'd approached. Call it familiarity, or instinct. Whatever. He knew Natasha and Natasha knew him.

Taking a deep breath, Clint slowly turned and took in the sight of his best friend, who he hadn't seen in over three years. She was wearing dark clothes that could be construed as either casual or combat suitable. Her hair was shorter than before, and slightly wavy in a way that very few people knew was its natural appearance. She looked good; like she'd just come back from an easy combat mission.

"Hello Clint."

"Nat."

There was silence for a moment as the two friends took each other in. Knowing that stalling wouldn't make anything easier, Clint decided to start the ball rolling.

"I... I made a mistake, didn't I, Tasha?"

Natasha gave an almost imperceptible sigh of sadness and regret. "We both did, Clint. But you should have come back. You should have never picked a side based on Steve's word alone."

"I'm getting that now." Clint gave a small, rueful smile. "There is a lot more to this than I thought, isn't there?"

Natasha's head tilted slightly in acknowledgement. "Yes. I think there's more than any of us know, but from what I do know... You're going to feel sick for a while when you find out. I did."

Clint gave a shudder at that. He was scared to find out what she knew, but at the same time he felt that he deserved it. "I guess it's my own fault for doing a job without doing my own research. It wasn't a job at the time, you know? It was a loyalty mission."

"It's still your fault for taking a loyalty mission from one side of the spectrum without checking the other. Clint, you chose a side without knowing what you were getting into because you were doing it for a friend. That is understandable, but I am upset that you chose a side without knowing what you were getting into when both sides contained friends. You took Steve at his word and you didn't ask Tony - you didn't ask me - what was happening from our end. Clint, I'm angry about that that. And I can't trust you again just yet. Don't fuck up like that again."

Clint nodded in acceptance. She was right in her assessment and he was big enough to acknowledge that he had screwed up when he had come out of retirement for Steve. "I'm sorry."

"I am, too."

Clint hesitated before he spoke next, unsure of whether he was pushing it. "You're not just here for me, are you?" Technically it was a question, but it was spoken like a statement.

Natasha gave no response, which proved Clint right.

"Things are about to get glacial, aren't they?"

This time Nat's face went blanker than he'd ever seen it. He looked right into her eyes and all he could see were the dark eyes of a spider. Faced with those eyes, Clint felt the sort of hopeless acceptance that one feels when trapped in a tundra in the dead of winter. When there is no shelter or means to prevent freezing, and no escape because everything looks the same - just an endless expanse of white as far as the eye can see. Clint had once seen the effects of Natasha's Ice Stare when she had saved him from one of the people who ran the Red Room, but feeling it... That was something else entirely.

"Well, I guess we're about to find out that you can't outrun a Russian winter."

~0~0~0~0~0~

Steve woke to the feeling of a cold blade on his neck. He was allowed a few moments where he felt his grogginess slip away to be replaced by pure terror and adrenaline at the implications of a knife being held to his throat, before a voice - barely recognisable with its wintery tone - spoke near his ear.

"Rogers."

He gasped in surprise. "Natasha?! What are you-?"

The knife pulled away, but Steve could still feel its freezing metal against his throat. He quickly jumped up to face the Black Widow in his room, but by the time he had turned around she was gone. Steve might have thought that he'd imagined the encounter, but van Dyne's words earlier that day as well as their initial reception, made him decide to play it safe. Walking into the common room, he was met by the sight of Natasha's back, framed by the large window which displayed a dark, cloudy night with no sign of wind and the only light coming from the moon's weak attempts to bypass the clouds. It was a beautiful, dramatic image. It was also terrifying.

Before he could say anything, however, the sounds of his nervous team approaching the same way he had, became apparent. Before long he saw Wanda, Sam Scott and Bucky approaching. Wanda looked particularly anxious, but Steve thought it was unlikely she'd received the same wakeup call that he had. Sam was looking understandably wary, while Scott seemed confused and terrified. Bucky was the only one who looked part-way at ease, but considering his experience with HYDRA, Steve figured that he didn't fully understand the situation.

After a few moments where the four newcomers noticed Natasha, Steve realised that there was no sign of Clint. Before he could say anything, though, he heard Sam direct a question to the counter in a low, wary voice.

"Clint? Do you know what...?" Steve turned and saw the resident archer perched, still and silent, on one of the stools. He didn't move or respond to Sam's question, instead staring straight past Natasha and out the window, into the night.

Before Steve could repeat Sam's question, Natasha began speaking.

"He was my family too, Rogers. He still is." There was a pause before Natasha continued in her dangerously cold voice. "We all consistently screwed him over - all of us. And he was still the one who fought the hardest, shouldered the burden of all our mistakes and cleaned up our messes. He was still the one who put the people first and fought for them - who adapted for them. We gave Tony impossible situations and he did whatever it took to get the best outcome for everyone. He made the hard decisions - the ones that we couldn't or wouldn't be able to handle - and he was amazingly good at giving us back workable situations, but we still criticised him for not making things perfect for us. Until it all came to a head with the Accords."

Steve stepped forward to defend them. "Natasha, no. That... That's not what it was. Tony was just... We didn't do that to him. It was his own choice and, to be honest, he could have done a lot better in some of those situations. And the Accords weren't... They weren't like that. They weren't necessary. We could have governed ourselves just fine without risking ourselves by putting us and our abilities in the hands of the government - of people like Ross." Steve looked at his team, but all except for Wanda were looking at where Natasha hadn't moved. None of them responded in reassurance, and Wanda only looked to him for a second before returning her gaze to the red headed assassin. Why weren't they...? It didn't matter, he could think about it later.

Natasha's silence had shifted. It felt like the cold when night first fell in winter back in the 1940s and he'd just been a skinny, sick kid. Eventually she spoke again.

"That's not true. It wasn't just about us, either. It wasn't about us giving up our rights. It was about giving the people we were supposed to be protecting their own rights. It was about being able to save more lives by becoming more effective and less volatile. We were unsustainable the way we used to operate, but now... Well, you'll see what we are now. It works. But I'm not here about that right now. I'm here to express my displeasure and give you the one warning you have a right to."

Steve opened his mouth, prepared to further argue his point, but was cut off by Clint.

"Don't. Just... don't interrupt her."

"Rogers and Barnes. I don't know what exactly happened in Siberia. None of us do, except Tony, obviously. I know that it was your shield and that it was your fault. I can guess that you fought, and I don't know what you did to make him attack you, but it must have been bad. I don't really care whose fault the fight was, because I know that it ended with the two of you running off to Wakanda. You left him with internal bleeding and broken bones in a dead suit in the middle of a supposedly abandoned HYDRA bunker in the middle of nowhere, Siberia. He had no way to communicate, and you left him." Natasha turned around then, and Steve wished that she hadn't, because he could feel the pure, frozen fury emanating from her dangerous figure. He didn't even need to see her clearly to be able to feel the penetrating ice in her eyes as the cold and hopelessness of winter ate at his bones.

"And I was there, with Pepper and Vision when FRIDAY told us that she'd lost contact with Tony and that she feared for his life. Because you were now hostile. I regret letting you both escape at Leipzig so, so much. I regret leaving Tony to handle everything else - yes, I ran away too. But I came back. And now you're all back, so I'll give you this warning only once - to all of you. If you ever try and manipulate or use guilt tactics or anything else like that again on Tony again, no one will be aware that it was murder that resulted in your death. If you ever betray him or hurt him again, then no one will find your corpses. Simply because no one will be able to mistake the wounds for anything but murder. You've all been given a second - or even third - chance. Don't fuck it up." Everyone was completely still as the Black Widow walked out of the room; the coldest point of a winter night; dangerous, patient and likely to return again in the future.

Steve always hated winter. Probably because it scared him.

~0~0~0~0~0~

Sam Wilson had always treated Natasha Romanov with the respect that her skills deserved. He had always known that she was a warrior and had seen and done too many things in her life for her to ever not be dangerous. He was man enough to admit that she had scared, frightened and even petrified him once.

But she had never terrified him. Until tonight.

What she had said - what she had been... It wasn't something that he had realised anyone was capable of. Nick Fury had never instilled primal, animal fear in him. She was a pure, untethered force of nature. Except she wasn't. Because nature didn't feel - winter didn't have emotions or motives. Natasha Romanov was winter, but she was undeniably human. And that was completely terrifying.

Sam, of course, was running out of reasons to stall questioning Steve about everything that had happened in Siberia. It had been mentioned a few times, but he was still finding it inconceivable that Cap would abandon Stark, whether they were enemies at the time or not, in a HYDRA bunker. He must have had a reason, right? He must have had a really, really good reason to do something as despicable as that - something that went against every value that soldiers were supposed to follow. The full story hadn't been told yet, so Sam determined that he wouldn't have an opinion until he had all the facts.

'That's not what you did last time Cap told you to do something. You didn't have all the facts then either, and you were willing to fight a war,' a traitorous voice in the back of his mind spoke. It sounded a lot like his mother, making Sam cringe with shame.

The problem was, with each new confrontation they were faced with, the more reluctant Sam was to find out what had really happened in Siberia - what he'd really fought for. He knew it was cowardly to hide from knowing the consequences of his actions - or inactions, as it may be - but he had a feeling that he really wouldn't like what he found out.

Trying to distract himself from the direction his thoughts had taken, Sam took in how the others were faring. Barnes was the only one showing any semblance of calm, and while Sam could have written that off as confidence resulting from his past in HYDRA, he could also make out respect and understanding in his gaze. Wanda was looking shaken, but probably not as worried as she should have been, likely because she believed that Natasha wouldn't be able to follow through with her threat. Scott was pale and clammy, and looked like he was feeling sick, which was completely understandable. Steve, predictably, had an air of almost palpable disbelief. Whether that was because of Natasha's points about the Accords, her opinions about Tony, her terrifying - but clearly true - threat, or the loss of her loyalty, Sam really couldn't tell. It wasn't until he looked to where Clint was seated that he was surprised by what he found, though.

Clint hadn't moved the entire time and he was still looking out of the window at the same point in the sky, but his gaze had altered so he seemed more aware. His lips had twisted into a small smirk.

"Clint? What's up?" He questioned, drawing the others attention to the archer.

Clint looked at him, eyes dark and the smirk still present. "I'm just thinking about what Nat said before you all got here. She said that she'd bet on Banner scaring the shit out of us." He gave a brief, dark laugh. "I'm really looking forward to it. Man," he laughed again and rubbed the back of his neck, "we screwed up big."

"Don't say that, Clint." Steve, who had broken out of his frozen state, admonished. "We did the right thing!"

"Yeah, well, I'm not sure who it was the right thing for, anymore."

Steve drew himself up and a look of righteousness crossed his features, but before he could deny Clint's clear challenge of their cause, Scott, who still looked shaky, asked Clint a question in a trembling voice. "Wha- Um, what was...?"

"What was that?" Clint finished for him and Scott nodded and mumbled a "yeah". Clint's smirk grew and his eyes went distant, clearly seeing something from another time and place. "Rage makes fire hotter, as we saw - hm, yesterday now - morning, and fury makes ice colder. I learned that lesson a long time ago, and now that you've learnt it, make sure you don't forget it. And do not - do not - doubt that any threat Tasha makes when she's in that state will be followed through. I am literally the only one in this room who she won't actually kill. Do not doubt it."

The sincerity of Clint's explanation didn't shock Sam. After witnessing Natasha's warning, he knew that he was right. The only thing that Sam wasn't sure about at this point was if Natasha would be faster than all the other people that they'd pissed off and been threatened by so far if they screwed up. It seemed that he wasn't the only one knew that Natasha wasn't joking.

"If fury makes ice colder, then that, right there, was a glacier." Barnes said, surprising Sam who had expected him to remain silent. Clint directed his smirk to the other former assassin. Wanda was looking more thoughtful and nervous now, Scott was more assured and steady, but Steve was staring at Barnes with a frown on his face implying that he still doubted that Natasha would try and kill him if they didn't heed her warning.

Sam just hoped that they wouldn't freeze.

~0~0~0~0~0~

"Jesus, she's scary. That was so worth getting up at freaking 1am for."

"It's 3:24AM, and you weren't asleep, Boss. You were in the lab and I was trying to blackmail you with decaffeinated coffee to get you to go to bed like a normal human being."

"Ah, semantics. Send a copy to Patches and Agent with the tag, 'You both owe me twenty for finding proof that Natasha does use dramatic flair, plus another fifty for catching Clint reciting poetry'."

"Of course, Boss."