Tony
Tony's nightmares are a constant companion when he forces himself to sleep, though they seem to change every time.
Sometimes he'll see Yinsen die, over and over, as the weight of his failure pierces his heart before the shrapnel gets a chance.
Sometimes he falls through a portal, clinging to consciousness and facing a sickening drop into oblivion without getting the chance to hear Pepper's voice one last time.
Sometimes he hears his mother's choked cries for his father before a dead-eyed assassin puts his hand around her throat, following orders that faceless men have planted into his brain.
Mostly, however, he's reminded of the vision that led to the spawning of Ultron. No matter how many times he tells himself that what he saw was a fabrication meant to frighten him - one that had doubtless done its job - the sight of his team-mates lying broken in the ruins of what was once their home is fused into his brain. Steve doesn't wake up for one final, choked accusation anymore though; instead Tony is truly alone and facing an army he can't hope to beat, and there's nothing he can do to save his friends or his world.
If such a devastating future truly awaits him, he hopes the end comes quickly. He's experienced the fear of knowing there's nothing to be done enough times to know he has no wish to endure it again.
When he wakes, it feels like someone has been dancing on his chest for all the effort it takes to draw a breath, and he'll instinctively turn to Pepper only to see the other side of the bed is empty. What pain this causes is buried when he stumbles into the bathroom and splashes cold water on his face, before making his way to his lab in order to lose himself in his machines.
He has a war to prepare for, after all.
Bucky
All he can hear is screeching metal as the floating helicarriers tear themselves to pieces, and though he thinks he should be burning from the heat of the nearby flames, all he can feel is ice clinging to his bones. For all he knows, he could be back in cryo – lost in time for countless years before being put to good use again – and it's only the sharp pain in his dislocated arm that makes him think otherwise.
A beam collapses onto glass and ends up falling into the waters below. He feels the floor shake beneath his knees, and a sickening jolt in his heart as he thinks he too may fall (not for the first time, he remembers now) but the surface beneath him remains solid despite the barrage falling upon it. It's with this realisation that he breathes again, and looks down at the broken man in his grasp.
His breaths cease once more, as if someone has plucked the lungs from his chest, and he looks into eyes which should not be familiar and yet are painfully so, and a uniform which seems lost in the past. The part of his brain that's aware he's dreaming screams at him to stop, but it's always silenced as primed metal continues its assault the Steve's face, leaving Bucky little more than an observer to his own actions.
The words that once saved him are left unspoken. By the time he regains control of his body and lowers his arm, those familiar blue eyes are empty and unseeing.
Bucky doesn't get the chance to scream before the floor collapses and he's falling.
Natasha
The world is grey.
She knows this room, though she has not stepped foot there for many years. The small, gloomy ballet studio with bullet holes in its walls is much the same as it always was, with the light streaming in through high windows doing nothing to wipe the greyness from her vision. One look in the mirror shows her clad in a dull uniform – the white muted and lifeless – and her pale face betrays no emotion even as it takes in the glint of the knife in her hand.
The woman by her side, who calls herself the Mistress, stands firm and silent. Her cheekbones are as sharp as the blade in Natalia's hand; her skin is stretched thin over a stern face and blue lips are pursed in impatience. She doesn't speak, but Natalia knows that when she does the voice will cut through her like ice as it barks out an order, and she hopes that the woman will continue her silence just this once.
The knife in her hand is cold. She can imagine it blistering her fingers and turning the flesh black if she holds it long enough.
It's when she feels a claw-like hand grip her shoulder that she tears her eyes away from the mirror and finally takes in the man tied to a chair in the centre of the room, his hands bound behind his back and his voice muffled by a gag.
Some nights it's Steve, others Tony or even Fury.
Mostly it's Clint.
She can feel her heart turn to ice as the order The Mistress has been holding back finally emerges from thin lips, and Natalia doesn't need to hear the words to know what is being asked of her. She knows she will obey – she always does – but as she moves towards Clint and sees how absurdly calm he is in the face of everything, her muscles scream in protest.
The knife descends, and grey becomes red.
Sam
Sam is always falling in his dreams. The wind slaps against his face as he descends, like tiny needles being jammed into his skin, and he keeps on falling while a broken scream gets trapped in his throat.
Not that it matters. The wail of the wind would cancel out any sound he made anyway.
It takes a long time to realise that he is not falling, but flying; that the wings are whole and functioning and that his body launching towards the earth is his intention.
Only when that realisation hits him does he finally see Riley.
He won't be able to save him. He never does. No matter how quickly he falls, Riley is always just out of reach, and even if he were able to catch him it would already be too late. The blast that knocked out Riley's suit also went through his heart, and no amount of training is ever going to be enough for Sam to fix that.
It seems to take hours for Riley to land, and seconds later Sam joins him.
Halfway across the world, he wakes in a bed that's just a little too soft and wipes unshed tears from his eyes before catching his breath and heading out for a run.
Steve
No matter how many miles Steve walks, there is never anything but dust beneath his feet. The world seems muted – he can't remember when he last saw blue or red or green – and even the sky is covered by a haze as if the dust is hiding the sun from view. Occasionally he'll walk by the broken husks of cars or the remains of what was once a home, and more than once he looks down to see the empty eye-sockets of a skull staring at him accusingly.
He supposes it was always going to end this way. Stark had called him immortal once, long ago, when he'd returned from what had seemed like a suicide mission, a little worse for wear but smiling in spite of it all.
Steve can't remember if that was twenty years ago or a thousand.
The abandoned shells of buildings start to crowd around him as he walks into the heart of what was once a city, though which one he couldn't guess, and shattered glass starts to join the dust beneath his feet. A lancing pain forces him to look down and realise he's barefoot, and a thin stream of darkened red trickles along the ground. The pain disappears quickly though, and is replaced with a numbness Steve now knows too well.
It's been a while since he's felt much of anything. Even hunger and exhaustion feel like old, estranged friends, and though he probably should feel loneliness considering everyone he's left behind, he knows that all he needs to do is turn and he'll see Bucky by his side.
It won't be long before he too vanishes into nothing. They may have survived for centuries, but the weakness of Zola's serum is starting to become apparent in the grey streaks of Bucky's hair and the growing slowness of his movements. One day he'll be gone, like the others, and Steve will be left in the ruins of a world he swore to protect, with nothing left to do but take another step forward.
He looks up, squinting against the feeble light that breaks through the fog, and is just able to recognise a tall building with a lopsided 'A' resting atop it. The tower is nothing but a shell now - shattered glass windows and deserted hallways leading to rooms which are caving in on themselves – but it's the closest thing they have to a home.
Steve looks to Bucky, trying to ignore the tiredness in the man's eyes, and repeats the mantra that has followed them since they were children.
In spite of everything, Bucky smiles.
A/N - I'm not entirely sure where this came from. I hope you enjoyed it though!
The title is taken from a line in Muse's 'Sing for Absolution' while the video provided some inspiration (visually) for Steve's segment.