Hello everyone! So this is a response to a prompt from httydlovena on Tumblr. I said I would try this for them, so here it is! I haven't decided if this is going to be a cohesive, full-chaptered thing or more of a series of scenes that I have in mind, hints this being part 1 and not chapter 1.

So the prompt was, in essence, if Tony had been snapped instead of Peter, and what follows that. Some of this is going to be different based on some of my logic, decisions, possibly headcannons, etc, but some of it will be largely the same, hints why I'm not sure how exactly how much I'll be writing out. But anyway, I won't drone on anymore. Thanks to everyone for reading, and I love you all 3000! Part 1 below the cut.

"Something is coming," Mantis says.

Her voice is barely a whisper, but it carries across the desolate planet as well as if she'd yelled it. Peter doesn't even look up. He scrambles over to Tony, helping the older man to his feet, and they both pretend not to notice how heavily he's leaning against him. Peter doesn't mind, and he doesn't want him to pull away before he's ready to. It wasn't exactly the hug he'd never got, but being close to him in any capacity was… nice. Even if this wasn't the ideal situation.

Far from it, actually, as he's about to find out.

They're barely approaching the wayward group again when Mantis disappears. It's not a flash, exactly; more like she melts away, leaving little pieces floating through the air as the only thing that remains of her in less than a second. If he'd blinked, he could have missed it.

Drax goes next, but he's slower. He calls out to Quill, who just stares at him in horror, as if he can't quite believe what he's seeing.

He still looks like he's trying to process it when he turns to dust, too.

Peter is aware of people talking - Mr. Stark, Doctor Strange, and the blue woman is still there as well. She's silent, for now - at least he thinks. Her lips aren't moving. But he can't really hear anything through the blood pounding in his ears. Is it fear? Adrenaline? A sign that he's going to be next? He doesn't know.

Nothing quite brings you back to reality like the feeling of the person leaning on you starting to move.

No, not move. Disappear.

Peter whirls. Mr. Stark falls on his knees the moment he lets go of Peter, but Peter is there, instantly, gripping the elder hero's arm as if that alone can keep him from going. "Mr. Stark?" His own voice is weak and wobbly, unfamiliar even to his own ears. "Please-"

"Listen to me, kid," Mr. Stark interrupts. His face is streaked with blood and ash and dust, and each one assaults his senses as the man leans closer, pressing his lips to his forehead gently for just a moment. Peter wants to close his eyes, to lean into the feeling, but he's too afraid the moment he does it will all disappear. "It's okay. You're going to be okay. I promise."

He can't promise that, and they both know it. Peter could be next. Even if he isn't, he could be trapped here, or left adrift in space. He may never get home again. He may never see May again, or his friends - if they're even lucky enough to survive. He's not entirely sure what's happening, but Thanos made his goals pretty clear.

Half of everyone. He doesn't know how he did it, but he obviously has.

Peter blinks back tears, squeezing Mr. Stark's arm so hard that he knows it has to hurt. But he can't stop it, can't loosen his grip, and it hardly matters when it turns to dust under his fingers.

His eyes snap to it, the dust floating where the limb should be, sweeping slowly up the rest of his body, and he can't stop the tears from spilling over. Mr. Stark tilts his head back up, his hands so unexpectedly gentle, and the tenderness in his eyes is like a knife to the gut. "Mr. Stark," Peter chokes. "Please, please don't go."

Mr. Stark just shakes his head. "I'm so sorry, Pete," he whispers. He reaches up to wipe a tear from his cheek.

His fingers make contact for a split second. Peter closes his eyes, trying to memorize the touch and simultaneously make reality disappear.

When he opens his eyes, reality is still there. But Mr. Stark is gone.

Sobs tear their way up his chest. He falls forward, right into the pile of dust where his hero used to be. The pain is immense, so much so that for a moment he wonders whether he's actually going to go too, if he wasn't spared after all.

But no. He knows this pain. It's the same pain he felt when his parents died. Then again when Ben died.

Every time he thinks he's shaken it, it comes back.

"Kid."

Peter flinches and looks up. His senses are all screaming, and his eyes are wet and wide. He's still sitting in the pile of dust that used to be his mentor, and yet- there's only one person who calls him that, and he can't help but hope-

But it's not an undusted Tony Stark that leans over him. It's the wizard again. Doctor Strange.

Peter doesn't bother to wipe his face. Sadness gives way to fury at the sight of the other man. The one who gave him the stone. Who did this to them, made this all possible-

Strange reads the anger on his face. His face softens almost imperceptibly, and he sighs a little as he kneels down beside him. "I know. I said I wouldn't, and I did, and you're confused and upset, but there's no time to explain. The mirror dimension can only delay the inevitable for so long."

"Mirror-" Peter looks around, confused, and suddenly realizes exactly why all of his senses are screaming. They're in the same place, but it looks… different. Shimmering and refracted on all sides of him, and it's not just because of how wet his eyes are.

"Peter," Strange says, drawing his attention back to him. "I did what I had to. You're not going to understand right now, but you will, eventually. Listen." He puts a hand on his shoulder, and Peter flinches again, unable to help himself. The familiar touches, plus the fact that his senses are in overdrive, make it all too painful, impossible not to react. "I can't hold on much longer. When I let us out of here, there'll be a portal open. I need you to go through it. It'll get you back to Earth, where you'll be safe."

Safe. The word resonates something in him, and he looks away. "Safe? I don't think anywhere is safe, not anymore. And what's the point?" He gestures wildly around them. "We lost. It's over."

"It's not over," Doctor Strange says firmly. "This is just the beginning. But only if you do what I tell you to, do you understand? You have to-" He stops, straightening quickly and stumbling back a few feet. "Dammit. We're out of time."

"What?" Peter stands up too, instinctively reaching out to steady him. "I don't understand. What do I have to do?"

"Just-" Strange grimaces, nearly doubling over in front of him. "Go through the portal. You'll figure out the rest."

Peter opens his mouth to protest. This is all too much. He doesn't understand, and he can't pretend that he does. Some part of him wants to listen to Doctor Strange, to believe his assurances that this isn't over, that they can still win, but things look pretty desolate and he's covered in the dust and blood of one of the last few people in the world who gave a shit about him with no guarantee that the others are even still alive. What's the point in going back to Earth? What's the point in any of it? Dying out here would be easier. He wishes he'd been one of the ones to go. He'd have given himself for Mr. Stark in a heartbeat.

But he doesn't get to say any of that, because then the world around him literally shatters, and he instantly knows he's back in real time. There's the telltale hiss of a portal opening in front of him, and he knows he should move, should go back through it, but he just can't find the strength.

"Kid." Strange's voice again, low and pleading.

Peter closes his eyes against it. He just can't.

But Strange isn't talking to him. He'd forgotten about the blue woman, it seems, but she hasn't forgotten about him.

He senses more than hears or sees when Strange goes. The portal is open for a split second after his disappearance.

In that split second, arms circle around his torso, grabbing him tightly, and yank.

There's the sensation of freefalling, and he's barely gotten used to it when they slam into solid ground, the cold metal of her partially inhuman form slamming into him.

It hurts, but he barely registers it. His senses are too busy being assaulted by the hellscape that the world has turned into around them.

Shrieking. Honking. Screaming. Crying. Alarms. Metal on metal. The smell of blood, sweat, tears, metal, antiseptic, smoke, but also flowers, grass, the fresh air-

He can feel the grass under his hands, the metal of the nanotech suit is too cold and hard against his skin-

He barely rolls onto his knees before he's retching. He throws up everything he could possibly have in his stomach, then dry heaves for another good few minutes.

Then he collapses, and it's days before he knows anything more.