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They were losing. That much was certain. The enemy was some kind of magician/tech user, and nothing they had could even get close to him.
To make matters worse, he had some kind of magical animals under his control. Twice the size of the Hulk. Bullet-proof. Repulsor blasts barely affected them.
They'd been fighting for just over a full day, already. Everyone was showing signs of tiring, but SHIELD couldn't afford to send in normal operatives to combat the threat. They'd just be fodder.
So the Avengers pushed on, because it was what they did.
The Hulk was making the most progress, tearing the beasts literally apart whenever he could get a handhold. And of course, the enemy in charge targeted him.
They watched the flash of light strike the enormous green body and for a moment, nothing happened.
The rest of the team held their breath, hoping.
But then the Hulk fell with a pained roar, and as he fell, he started to change. Before the dust fully settled, the rest of the Avengers could clearly see Bruce's form in the crater the Hulk had made.
The enemy took aim again, and Tony just managed to get in the way.
The spell—or whatever it was that the enemy was really using—exploded on contact with the suit and tore it apart. Tony fell in a flash of red and gold and smoke.
Bruce was moving before he was even fully aware. Tony was falling. Again. And he couldn't change into the Hulk.
Tony had taken the hit meant for him.
Bruce tripped over rubble and debris, not even paying attention when a stray piece of twisted metal gouged his thigh, sliding to a stop only when he was at Tony's side. He dropped to his knees and…stopped.
Tony's eyes were open, and he was looking at Bruce, but Bruce couldn't do anything. His chest of was a mess of twisted metal, and the reactor was destroyed, it's light completely snuffed out.
"Tony…god, Tony…" Bruce's hands shook over Tony's chest. He hadn't felt so useless in years.
"Hey Bruce…" Tony's voice was a ragged whisper with a wet edge, and the sound sent a thrill of panic down Bruce's spine.
He moved his hands to cradle Tony's head. The faceplate was missing, and the helmet itself was torn to shreds, barely holding onto Tony's head.
"Tony, don't talk. You're going to be okay, but you can't talk, okay? Just stay still. Please. You'll be okay." Because he had to be. Bruce's throat constricted at the idea of Tony not being okay. He could feel the hot pressure of tears in his eyes, but couldn't bring himself to close them. He didn't care if he started crying. He couldn't look away from Tony's unfocused eyes.
"You're a horrible…liar, Bruce." And just that one sentence had Tony coughing, a trickle of bright red blood working past his lips to stain his chin. Bruce absently wiped it away with his thumb, shaking his head the whole time.
"No. No. You're going to be okay. You just have to stay with me, Tony. Please." He was trembling, and he could see his tears slashing onto a piece of armor that had managed to remain intact. "Please." His voice was wrecked, but he didn't care. He couldn't bring himself to worry about his emotions, or controlling them, because the Hulk was silent in his mind for the first time since his accident.
A cold, shaky hand lifted to Bruce's face, and Bruce could feel the sticky dampness of Tony's blood on the man's palm. He cupped it to his face with one of his own hands, the other still gently stroking Tony's jaw.
"Shoulda told you…" He coughed again, and Bruce could feel drops of blood splatter on his face, but he couldn't care. He whispered Tony's name again, but Tony ignored him. "Bruce I…I love you."
And Bruce couldn't have stopped the broken sob that left him even if he'd tried.
He clutched the hand he was holding against his face and shook his head again, more fervently.
"I love…God, Tony. I love you too. Please. Please don't leave me. I can't—" His words were lost in another ragged sob, and the tears flowed down his face without reserve.
"You can." Tony's words were soft, his lips coated in blood, and Bruce just kept shaking his head. "You can. You will."
"No. No, I can't. Tony, I can't. Please. I need you. I need you with me. I can't…I can't come back from this." And he couldn't, knew he couldn't. Tony was his anchor. Tony was the reason Bruce hadn't run off already. Tony was the reason Bruce didn't think about the phantom taste of metal on his tongue or the ring of a single gunshot when he was alone.
Tony just gave him a small, sad, red smile. "Love you." And then he closed his eyes, and Bruce felt his heart stop.
"Tony? Tony! Tony, you can't go! You can't leave me! Tony!" And he was sobbing uncontrollably, his voice shrill with panic, but when he managed to steady his hand enough to feel for a pulse, there wasn't one.
He screamed and curled in on himself, over Tony, shielding him. Tony's name was a chant on his lips, even as he turned back into the Hulk.
Bruce gladly let him take over, gladly sunk into the almost-sleep that claimed him whenever the Other Guy was in charge of their body.
And for a time, Bruce Banner knew nothing else but pain and anger and grief and desperation, and he vowed to never wake up again.