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1.
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The Avengers had just returned from an especially grueling mission. Exhausted and tense, they had taken a brief break, swapping their combat suits for regular clothes, freshening up, and trying to shake off the adrenaline before heading into the meeting room. The atmosphere was heavy with fatigue and lingering frustration as they all took their seats around the long table. Tony Stark, as always, claimed the head of the table, his posture deceptively relaxed. A tense silence hung in the air.
Peter Parker shifted nervously in his chair, hands fidgeting in his lap, eyes darting between the older Avengers. Tony, noticing his unease, assumed it was typical teenage anxiety mixed with the aftermath of a chaotic mission.
“So,” Tony began, leaning back in his chair, crossing his arms, and letting his sharp gaze sweep the room. “Today… did not go well. At all. None of you seemed to know what you were doing out there, and frankly, it was chaos.” His voice carried both irritation and disappointment. “You all need to fix that.”
The memory of the mission flashed in everyone’s minds, coordinated strategies collapsing into confusion, missed signals, and mistakes piling on top of one another. The only one who had actually tried to keep things on track had been Peter, though Tony didn’t need to say it aloud.
“You guys are probably some of the worst team players I’ve ever worked with,” Tony continued, scanning each Avenger with a critical eye.
Steve finally lifted his gaze from the table, his brow furrowed. “Don’t you think you’re partly to blame too?” he said, a faint condescending edge in his tone. “If you hadn’t distracted me and Romanov, maybe things would’ve gone more smoothly.”
“Oh, so now you’re trying to pin the blame on me?” Tony shot back, leaning forward, voice rising slightly.
“We may all be at fault,” Steve replied, his tone icy, “but it was certainly your fault I ended up falling off the plane.”
Tony’s eyes narrowed, and he slowly rose from his seat, a dangerous glint in his gaze. “Oh, that’s what you think? Well, why don’t we look at the footage together, Captain Asshole?”
He started toward the projector, his strides purposeful, but then something strange began to happen. The edges of his vision darkened, the world around him starting to dim. Tiny black spots danced across his sight, and a creeping sense of nausea settled in his stomach. His legs suddenly felt unsteady, like they weren’t his own. Probably nothing, he thought, blinking rapidly.
But as he reached the projector and grasped the edge for support, the sensation worsened. The blackness at the periphery of his vision spread inward, swallowing the room. His ears rang slightly, and a cold sweat broke out across his forehead. He swayed, heart hammering faster than usual, his body sending warning signals he couldn’t ignore.
“Uh… you okay, Stark?” Clint’s voice came from behind, laced with concern.
“Yeah… su—super,” Tony tried to say, his words slurring slightly as the nausea hit full force. His knees buckled beneath him, and the table tilted unnaturally in his vision. Sounds distorted, the voices of the Avengers sounded muffled, panicked.
Then the last bit of light disappeared. Tony’s body gave way entirely, collapsing to the floor as darkness claimed him. Cries of alarm rang out around him, Steve and Natasha lunged forward, Peter scrambled to help, and Clint caught his arm just as Tony hit the ground with a thud.
His consciousness slipped away, leaving him suspended between panic and nothingness, his vision gone, the world fading to black.
-
Peter watched Tony stumble, his fingers gripping the edge of the projector like a lifeline, and he already knew what was coming. A small sigh escaped Peter’s lips. Only Pepper and he knew Tony had POTS, no one else could understand what was happening right now. Peter had learned about it after an incident in Tony’s lab, months ago, when Mr. Stark had become dizzy and nearly collapsed. That night, Peter had scoured every medical source he could find, reading about autonomic dysfunction, presyncope, and fainting until the first rays of sunlight crept through his window. He understood now why Tony avoided heat, why he sometimes seemed unsteady, and why fainting was not impossible, even for someone like him.
Peter’s heart rate spiked as he saw Tony’s legs wobble. He wanted to leap forward, to grab Tony before he fell, but he froze for just a moment, calculating how best to help. Then Clint’s cautious, hesitant voice cut through the tension.
“Uh… you okay, Stark?” Clint asked, frowning as he took a careful step forward. His eyes flicked between Tony’s pale, sweaty face and the way his body swayed precariously.
“Yeah… su—super,” Tony replied, but his words were strained, almost slurred. His voice wavered with the effort of staying upright, and his hands gripped the projector with more force than necessary.
And then it happened. His knees buckled suddenly, as if they had never been strong enough to support him at all. Tony toppled forward with a loud thud, hitting the floor chest-first, the edges of his vision filled with black spots and fading light. A low groan escaped his lips, muffled but audible, and Peter’s stomach tightened.
“TONY!” Peter yelled, jumping up instinctively, adrenaline coursing through him.
The rest of the Avengers reacted instantly. Any exhaustion or frustration from the mission evaporated in a second, replaced by sheer panic. Thor, as always, overreacted, but in his own uniquely concerned way.
“It seems the Man of Iron has finally fallen! What shall we do?” Thor exclaimed, his voice unusually high-pitched, like a child trying to imitate a commanding tone. Stress always made Thor sound a little off, and now his concern bordered on dramatic theatrics.
“What the hell just happened?” Steve shouted, dropping to his knees next to Tony. His hands hovered over Tony’s torso, and his eyes were sharp, scanning for immediate danger. “FRIDAY, what’s his heart rate?” Steve demanded, voice booming. Banner crouched on the other side, fingers pressed against Tony’s wrist as he tried to gauge the situation.
“Mr. Stark’s heart rate is currently 170 beats per minute,” FRIDAY responded, her calm, cheerful voice cutting through the chaos. It was almost unnerving, completely mismatched with the alarm in the room.
Peter didn’t hesitate. He grabbed a chair from nearby and quickly placed it in front of Tony’s legs. “We need to elevate his legs,” he said, his voice tight, almost breathless with urgency. “It… it helps blood get back to the brain.”
“What? That’s way higher than normal!” Steve exclaimed, jaw tightening, clearly struggling to reconcile what he was seeing with what he knew about human physiology.
Peter gently lifted Tony’s legs, placing them on the chair and holding them steady to prevent them from collapsing again. Tony’s arms twitched slightly, his fingers brushing against the floor, and his body shivered as the faintest tremors ran through him.
“Uh… what are you doing, kid?” Clint asked from behind, suspicion and confusion in his voice.
“Nothing… just… thought it might help,” Peter replied, stumbling over his words. His heart pounded as he stayed close, making sure Tony’s legs remained elevated while supporting the subtle weight shifts in his body.
Tony’s eyelids fluttered. A low, groaning sound escaped him as he slowly became aware of the ceiling above. His vision was still dim, black spots clinging stubbornly to the edges, and the world felt warped and distant, like he was moving underwater. His arms felt heavy, his legs like lead, and each small movement required more effort than it should have.
Peter stayed low, quietly murmuring encouragement. “Easy… just breathe, Mr. Stark. You’re okay… just stay still.” He didn’t explain anything; the others didn’t need to know the secret, and he didn’t want to draw unnecessary attention.
The room was a mix of chaos and tense observation. Steve crouched beside him, attempting to keep Tony stable while barking orders to Banner. Clint hovered nervously, unsure whether to help or stay out of the way. Thor, still looming like a giant guardian, muttered under his breath about Odin and fallen heroes, hands almost trembling as he hovered protectively.
Meanwhile, Tony’s body slowly responded. The color returned to his face in faint streaks, his breathing steadied, and his eyes slowly focused, though the lingering black spots made him blink repeatedly. He groaned again, more softly this time, and Peter gently held his legs, careful not to let him overexert himself too soon.
The room remained silent for a heartbeat, each Avenger frozen in a mix of worry, confusion, and the unspoken acknowledgment that Tony Stark, brilliant, stubborn, infuriating, had just been humbled by his own body.
-
Tony’s eyes fluttered fully open, hazy at first, black spots still lingering in his vision. He blinked rapidly, trying to focus on the chaos around him. The room smelled faintly of coffee and lingering sweat from the mission, mixed with the sterile scent of the projector.
“Ugh… what happened?” he groaned, his voice hoarse. His hand brushed across the floor as he pushed himself into a semi-sitting position, Peter gently holding his legs on the chair.
“Tony! You just—” Steve began, but Tony cut him off, raising a hand weakly.
“Relax, Captain Perfect,” Tony said, attempting to sit up fully. “I’m fine. Really. It’s just… low blood sugar. Nothing to see here.” He tried to laugh it off, forcing a wobbly grin, but the tremor in his hands betrayed him.
Steve’s brow furrowed, arms crossed, clearly unconvinced. “Low blood sugar? Are you telling me that your heart racing to 170, going pale, and collapsing flat on the floor… is just because you skipped a snack?”
Tony waved him off. “Yeah, exactly. Sugar. Probably that donut I forgot to eat this morning. That’s all. Totally normal. No one panic. I repeat: no one panic.” He gave a shaky thumbs-up, though it was more a plea for them to stop hovering.
Thor, still looming like a slightly confused guardian, tilted his head. “Tony Stark… thou art pale as a frostbitten elf, thy legs tremble like reeds in a storm, and thy pulse quickens as though thou hast faced ten battles… and yet you claim it is merely food that hath failed thee?” His deep voice carried both skepticism and genuine concern.
Tony coughed nervously. “Yup. Sugar. Simple, boring human problem. Nothing dramatic, promise.”
Clint raised an eyebrow. “Right… because collapsing in front of the entire team is totally normal for someone whose only issue is ‘forgot breakfast.’”
Peter stayed quiet, holding Tony’s legs, knowing that explaining POTS now would only make things worse. Instead, he focused on keeping Tony stable, gently encouraging him to stay seated while the rest of the Avengers buzzed around.
Banner crouched beside Tony, checking vitals again. “His heart rate is still elevated. Low blood sugar doesn’t usually spike it this high. Are you sure you’re okay, Tony?”
Tony groaned again, slumping slightly against Peter’s hands for support. “Yes, yes, Banner. Totally fine. Probably just… adrenaline from the mission and a minor sugar dip. Happens to the best of us,” he muttered, voice strained but trying to stay casual.
Steve, still unconvinced, shook his head. “I don’t know, Stark… this doesn’t add up. You don’t just pass out like that unless something else is going on.”
Tony forced another laugh, wincing as his body protested movement. “Look, I appreciate the concern, really, I do. But I’m fine. I’m Stark. I survive worse than a low-sugar crash. Just… maybe get me a donut anyway. For science.”
Thor, still hovering protectively, muttered, “Aye… yet I shall remain vigilant. The mortal body is strange and treacherous indeed.”
Peter let out a small, silent sigh of relief. For now, Tony was stable. The other Avengers remained suspicious, questioning, hovering, and planning interventions that would never come, while Peter silently bore the knowledge of the truth, the secret about Tony’s POTS tucked tightly inside.
Tony leaned back slightly, groaning, clearly embarrassed but trying to regain his usual bravado. “Okay… let’s all just pretend this didn’t happen, shall we? And no, Steve, this is not the start of a new team-building exercise.”
The room remained tense, but the immediate danger had passed. Peter gave Tony a quiet, reassuring look. He knew it would be a long time before anyone fully understood, if ever, but for now, Tony was safe, and that was enough.
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2.
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“FRIDAY, get Natasha down here,” Tony muttered, his voice carrying across the wide training bay as he sank onto one of the benches along the wall. His elbows rested loosely on his knees, a careless pose that didn’t quite hide the fatigue weighing on his frame.
On the central mat, Steve and Clint were sparring. Steve was clearly holding back, deflecting a rapid series of kicks from Clint with effortless precision. His expression remained calm, controlled, the way it always did in training. Clint, on the other hand, was breathing harder, his brows furrowed with concentration.
Off to the side, Banner observed quietly, still dressed in his lab coat. A pen scratched across the notepad in his hand as he made meticulous notes. He hadn’t explained why he was documenting sparring sessions, and Tony hadn’t cared enough to ask. Bruce did his science thing; Tony let him. Simple.
“Heard you wanted me?” Natasha’s low, even voice suddenly spoke from Tony’s left.
He flinched before twisting his head. She’d appeared out of nowhere again, her presence as silent and unnerving as ever. By now, he really should be used to it, but Natasha Romanoff had a way of keeping even him on edge.
Before he could answer, a dull thud and a pained grunt drew his gaze back to the mat. Clint was flat on his back, blinking up at the ceiling.
“Sorry, Clint,” Steve offered sheepishly, rubbing the back of his neck.
Clint pushed himself up with a groan. “Don’t worry about it. You were pulling your punches anyway.”
Tony smirked faintly before glancing at Natasha again, only to find her right at his side now, standing close enough that he startled.
“Geez, Romanoff, put a bell on or something,” he muttered, pushing himself up from the bench.
One of her eyebrows lifted, but she didn’t dignify that with a response. Instead, she crossed her arms. “So, why am I here?”
“Sparring.” Tony’s reply was simple, clipped, as he stepped toward the mat. Natasha fell into stride beside him, her movements deliberate and fluid, like she was already calculating how she’d dismantle him in three moves.
“Go easy on me,” Tony added, climbing onto the mat. “We all know you could probably drop the Hulk if you wanted to.” He flexed his hands, knuckles popping.
He already felt a little lightheaded, but that wasn’t new. Exercise and his system didn’t exactly get along, his doctors called it orthostatic intolerance, but in Tony’s book, it was just another bug in the Stark operating system.
Natasha tilted her head, an amused smirk tugging at her lips. Then, without warning, she moved. Tony lunged first, aiming a punch at her shoulder, but she sidestepped with infuriating ease. Her counter-kick struck his side, forcing a grunt from him as he stumbled back.
They exchanged blows, but Tony knew the truth: Natasha was pulling her punches. She could’ve had him flat on his back in seconds if she wanted to. Still, he pressed on, determined not to give her the satisfaction of seeing him quit.
His chest tightened. His pulse was hammering faster than it should have, and the edges of his vision were beginning to fuzz. He brushed it off. Dizziness during exertion was normal for him.
He swung again, sloppy this time. Natasha ducked and swept her fist up into his ribs, sending him sprawling onto the mat with a loud thud.
“Aw, come on,” he groaned, wincing as he looked up at her.
“That was an easy one,” Natasha said evenly, both brows raised in challenge.
Tony rolled his eyes and scrambled to his feet. The instant he stood upright, he regretted it. His vision fractured into black spots, dancing and multiplying. His heart slammed against his ribs, so loud it roared in his ears. Heat rushed to his face, and sweat dripped down his temple.
Too fast. Too much. Sit down, Stark.
But before he could even steady himself, the floor tilted sharply. “Oh, fuck.” He mumbled. He immediatley dropped onto his ass, trying to not pass out.
His vison went completely black.
-
Tony hit the mat hard, his legs splaying out in front of him. Darkness swallowed the edges of his vision, his chest hammering like a jackhammer in his ribs. Sweat trickled down his face, and nausea churned violently in his stomach. His body felt both impossibly heavy and fragile at the same time.
“Tony!” Clint shouted, sprinting across the mat, eyes wide in alarm.
“What the hell? Nat, what did you do to him?” Clint demanded, crouching beside him.
“Nothing!” Natasha’s voice was calm but edged with concern. “We were just sparring. Like normal.”
Bruce was already at Tony’s side, moving with careful precision. He crouched low, feeling the faint tremor in Tony’s limbs. Checking his pulse at the wrist, he noted it was fast, but regular. He frowned. Not catastrophic, but concerning for someone who had just collapsed.
He grabbed his stethoscope and quickly slid the earpieces in, pressing the diaphragm first against Tony’s back. Lungs: steady, even. Good. Then he moved it to Tony’s chest.
Thud… thud… thud…
The heartbeat was fast, almost frantic. Bruce’s brow furrowed. “Huh… not dangerous, but definitely stressed.”
Tony’s eyelids fluttered open, squinting at the harsh lights of the training bay. His head felt thick and foggy, his vision still dotted with black spots.
“What the hell just happened?” he muttered, voice weak. “Where… am I?”
“You’re in the training bay. You fainted,” Bruce said, pressing the stethoscope lightly again. His heartbeat had slowed a bit, thankfully, but the rapid thump still suggested Tony had overexerted himself.
Tony groaned, sweat slicking his hair. His stomach flipped. “FRIDAY, get a medical team here.”
Clint froze. “Wait, already?”
“Yes, sir. Medical team will be there shortly,” FRIDAY replied, calm and precise.
Tony waved a hand irritably. “Cancel the medical team, FRIDAY. Seriously. Not needed.”
Bruce blinked, crouching closer. “Tony… we really should check you—”
“Just low blood sugar,” Tony interrupted, brushing off Bruce’s hand. He forced a grin, though his chest still felt tight and his legs trembled. “Nothing to worry about.”
Steve crossed his arms, skeptical. “You’re lying to us.”
“Not lying,” Tony shot back, tone sharp. Even as he spoke, the subtle aftereffects of the faint were clear: pulse still elevated, slight tremor in his hands, heat flushed across his face.
He glanced at the mat, letting his fingers brush it for stability, and then straightened just enough to issue a casual request. “Anyway… someone grab me some potato chips?”
Natasha’s eyes softened slightly, a mix of concern and exasperation. Clint muttered something about “this guy,” while Steve just narrowed his eyes, unconvinced. Bruce stayed close, his hand resting lightly on Tony’s shoulder, ready to intervene if he saw Tony collapse again.
Even as Tony tried to act casual, the subtle signs of stress were still there, fast heartbeat, flushed skin, lingering dizziness, but no one knew the real reason. And Tony wasn’t about to tell them.
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3.
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It had officially been three weeks since Tony had last fainted because of his POTS. He felt a rush of quiet gratitude each time he remembered this, three weeks without an episode was a personal record. Usually, he experienced fainting spells at least once, sometimes multiple times, a week. He didn’t know exactly what had changed, maybe the new medication adjustments, maybe the stricter self-care routines, but it didn’t matter. All that mattered was that this streak continued.
Right now, he was propped up on the couch in the common room, legs stretched out on the cushions, watching Star Wars with the Avengers. They had originally planned to watch The Hunger Games, but Peter had practically begged them for a Star Wars marathon, and eventually, everyone had given in.
Since the fainting incident in the training bay, the Avengers had been… unusually cautious around him. Extra careful. Hovering. Asking if he was “okay” every five minutes. At first, Tony had appreciated it. Now, three weeks in, it was starting to get under his skin.
“Mr. Stark?” Peter’s voice broke through Tony’s distracted thoughts. The boy sat cross-legged on the floor beside the couch, wearing his Spider-Man pajamas. His shirt was peppered with tiny Iron Man masks, a mash-up of his two favorite heroes. At the start of these movie nights, Peter had dressed up in full costume, mask, web-shooters, the works, but now, after months of comfort and trust, he had finally relaxed into casual pajamas.
After his Aunt May had passed away, Peter had moved into the room next to Tony and Pepper’s. Tony wasn’t sure he’d ever gotten used to hearing the kid call him “dad” by accident on his way out of the room. The sound had caught him off guard at first, leaving him frozen in the doorway with a popcorn kernel halfway to his mouth.
“Yes, Pete?” Tony said, shoving another handful of popcorn into his mouth and chewing thoughtfully. The rest of the Avengers were scattered around the room, mostly focused on ice cream and the occasional burger.
“Do we have any wheat cakes?” Peter whispered, curling his legs up on the couch and resting his chin on his knees. Tony knew why he asked. Ever since May had passed, wheat cakes had been his comfort food, a small ritual that reminded him of home, of family, of warmth. Tony didn’t ask questions. He just made sure the kid got them.
“I’ll go check, squirt. Be right back,” Tony replied, pushing himself off the couch slowly, trying not to draw attention to the sudden tightness in his chest.
And then it hit him.
That familiar, unwelcome sensation: presyncope. His vision blurred at the edges, his legs weakened like they weren’t even part of him, and a high-pitched ringing filled his ears. Three weeks. Three whole weeks, and it chose right now.
“Shit,” he muttered under his breath, panic prickling at the back of his neck. He tried to stumble toward the kitchen, tried to get out of the Avengers’ sight so he wouldn’t cause a scene, but the world tilted beneath him too fast.
Before anyone could react, he collapsed, headfirst, landing with a loud thud on the floor. Pain shot up from his nose, and the world went black.
-
Natasha’s instincts kicked in the moment she heard the heavy thud from the right side of the common room. Her chair scraped against the floor as she was already half-standing, left hand slipping toward the dagger strapped at her thigh. Before she could move further, FRIDAY’s voice cut through the dark.
“Alert: medical event detected. Turning lights on.”
The room was suddenly bathed in white light, harsh after the dim movie glow.
“What the hell is go—” Steve’s voice faltered as his eyes landed on the figure sprawled face-down on the floor. His posture stiffened immediately. “Tony.”
Of course.
Natasha exhaled sharply through her nose, annoyed less at him and more at the situation. With a resigned sigh, she released her grip on her dagger and strode quickly to Tony’s side.
“Again?” Bruce asked quietly as he pushed himself up from the couch and joined her, his movements calm but purposeful.
“Guess so,” Natasha muttered. She crouched down, her sharp eyes scanning over him. “Though I still don’t know why this keeps happening. Do you think he’s—”
“Dying again?” Bruce finished grimly. He knelt beside her, gently rolling Tony onto his back. A smear of red streaked across Tony’s upper lip. Blood dripped steadily from his nose, making the sight all the more alarming.
“What do you mean again?”
The voice came from above them. Instinctively, Natasha’s hand was back on her dagger, her body snapping into defensive mode. But when she tilted her chin up, she froze. Peter Parker was clinging to the ceiling, crouched like a spider, looking down at them with wide, worried eyes and furrowed brows.
She forced herself to relax, pulling her hand away again. “Kid,” she muttered under her breath, choosing to ignore him as she shifted her attention back to Tony.
By now, Clint and Steve had closed in, standing over Bruce and Natasha, their faces grim and unreadable as they looked down at their fallen teammate.
Steve folded his arms, trying to mask his worry with practicality. “Uhm… I guess we just wait until he wakes up?”
“No,” Peter’s voice cut in again, sharper this time. His eyes didn’t leave Tony’s face. “Lift up his legs.”
Bruce glanced up at him and nodded without hesitation. “Good idea, Peter.” Moving around Natasha, he crouched at Tony’s feet and raised both legs carefully, propping them higher.
Steve frowned, tilting his head. “Why?”
“It helps blood flow back to the brain,” Bruce explained simply, keeping Tony’s legs steady.
They didn’t have to wait long. Within a minute, Tony’s lashes fluttered, his eyes cracking open sluggishly. He looked disoriented, blinking hard against the overhead lights.
The Avengers stayed quiet, giving him a moment to orient himself. His breaths came shallow at first, then deepened as color slowly returned to his face.
“Fuck,” Tony groaned after a beat, rubbing weakly at his temple. His voice was hoarse. “Did I… pass out again?”
“Yeah, Tony.” Clint’s voice carried a note of exasperation, though there wasn’t true malice behind it. More curiosity than concern. “Are you ready to tell us what’s going on yet?”
“Nothing,” Tony shot back immediately, stubborn as ever. He swiped his finger under his nose, pulling it back to see the smear of blood. With a groan, he pinched the bridge of his nose and let his head drop back. “Great. Did nobody catch me this time? Seriously?”
Peter dropped from the ceiling with a soft thud, landing in a crouch. He straightened up, eyes sharp, jaw tight. “What’s this about you dying?” His voice cracked slightly, anger and fear battling inside him.
Tony’s eyes snapped open wider, caught completely off guard. His gaze shot to Peter’s, and for once, the genius looked rattled. “Uh… nothing. Who told him that?” His voice wavered, tired and defensive all at once, his mask slipping as he tried to regain control of the conversation.
But Peter didn’t look convinced.
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4.
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Tony pressed a hand dramatically against his chest, stumbling back a step as though someone had just taken a shot at him. His wide brown eyes flicked across the room, taking in the sight: the Avengers, Earth’s Mightiest Heroes, standing around in paper hats and streamers, looking about as intimidating as a kindergarten birthday squad. The entire penthouse was draped in colorful decorations: balloons taped to the walls, banners strung from the ceiling, and a faint shimmer of confetti still floating down through the air like glittery snow.
“Happy birthday!” they all shouted at once, voices overlapping in a chaotic chorus. Another burst of confetti rained down, courtesy of a cannon in Clint’s hands.
Tony blinked, lowering his hand from his chest with a confused frown. “Wait, hold on. Whose birthday are we talking about here?” His eyebrows shot up, suspicion creeping into his tone.
The group hesitated, glancing at one another, a ripple of uncertainty passing through them.
“Yours, Mr. Stark,” Peter finally piped up from the right, his voice earnest but a little nervous. He was grinning from ear to ear, his dark curls sticking out awkwardly under a crooked party hat. To make matters worse, or better, depending on who you asked, he was wearing a T-shirt plastered with an enormous photo of Tony’s own smirking face.
Tony stared. “…What?” he said flatly. “No, that can’t be right. My birthday’s in October.” He lifted his wrist and flicked his smartwatch screen to life, squinting at the glowing numbers. May 29th, 6:36 PM. His frown deepened.
He looked back up at them, still baffled. The room was alive with flashing disco lights. Tables sagged under the weight of pizza boxes, bowls of chips, candy, bottles of soda, and, most importantly, several very expensive bottles of alcohol.
“Uh, no,” Clint drawled, leaning lazily against the couch and pulling a party blower out of his mouth with a squeaky pffft. “Your birthday is today. May 29th. How do you not even know your own birthday?”
Tony blinked again, this time slower, like his brain was trying to reboot. “…Really? Huh.” He shrugged one shoulder. “Well, thanks for the party, but for the record, you guys nearly gave me a heart attack. Not the best odds with my medical history.” He raised a brow at them and, true to form, immediately made a beeline for the alcohol table.
“Mr. Stark! Wait!” Peter’s voice rang out behind him, bright and eager. The kid darted forward, nearly tripping over his own sneakers, clutching a small box wrapped in shiny red paper. A golden bow, customized with tiny Iron Man mask prints, sat proudly on top. Peter’s smile was wide and a little shaky, like he’d been practicing this moment in his head for days.
Tony froze mid-step, the sarcasm melting right out of him. His gaze softened as he turned, finding Peter standing there, holding the gift out with both hands like it was something precious.
“Kid…” Tony’s voice dipped lower, gentler. “You didn’t have to do that.” He took the box slowly, glancing over at the rest of the Avengers with a crooked smile. “What is this, huh? You trying to make the others look bad?”
“Mission accomplished,” Bruce muttered, arms crossed over his chest. His expression was deadpan, though the neon yellow party hat perched on his head ruined any attempt at seriousness. “We throw the guy a surprise party the size of a small wedding, and the only thing that makes him happy is alcohol and the kid.”
“Appreciate the pep talk, Banner,” Tony shot back, sending him a glare that didn’t quite land before he turned his attention back to Peter. The look in his eyes softened again, all the sharp edges dulling.
“Thanks, kid,” he said quietly, sincerely, as he accepted the gift.
Peter’s smile lit up like someone had just switched on the arc reactor in his chest.
-
“Okay, everyone! Let’s play charades!” Clint yelled over the background music, his voice cutting through the chatter as the Avengers gathered around the living room. Some perched on the couch, legs crossed, while others sprawled across the floor, trying to make themselves comfortable. Balloons and half-empty snack bowls littered the tables, and faint disco lights flickered across the walls.
“Who’s going first?” Clint asked, flashing a grin.
Tony, feeling slightly tipsy from a few glasses of wine, sank down onto the floor with a relaxed sigh, lifting his glass in a half-toast to nobody in particular. “I’ll go first,” Thor announced, rising from the couch like a colossus among mortals, towering over everyone as he strode confidently to the center of the room.
“Okay, here you go,” Clint said, handing the god a small hat filled with folded slips of paper, each with a different word written on it.
“Thank you for the hat, man of arrows,” Thor replied, his booming voice melodic, as he carefully set Mjolnir down on the floor beside him.
“Uhm…kay,” Clint muttered under his breath, tilting his head slightly in confusion.
Thor picked up the hat, placed it on the table, and extracted a slip of paper, opening it slowly as he read its contents. “Hm,” he murmured thoughtfully.
“So…are there teams?” Peter asked, shifting closer to Tony on the floor, his eyes alight with excitement.
“Nope,” Clint replied. “Everyone just guesses.”
“Okay,” Peter nodded enthusiastically, clearly looking forward to the game.
“Ready?” Thor asked, his wide grin practically lighting up the room. The Avengers nodded impatiently, trying to hide their skepticism at the god’s over-the-top demeanor.
Clint set a timer for thirty seconds. “Begin!” he called, pressing the start button.
Immediately, Thor launched into an array of elaborate gestures. His arms flailed dramatically, fingers pointed at imaginary objects, and his eyes tracked some unseen horizon. His enthusiasm was palpable, but completely indecipherable.
“Uh…driving!” Tony yelled, squinting at Thor, who shook his head slowly.
“Writing!” Natasha guessed next, her sharp eyes narrowing in concentration. Another shake of the head.
“Doing makeup!” another guess. Shake.
“Playing video games!” Shake.
“Flying a plane!” Shake.
“Ten seconds left, guys!” Clint shouted, raising a hand as Thor continued the increasingly bizarre hand motions, spinning and gesturing as if battling an invisible horde.
“Uhm…using Spider-Man webs?” Tony ventured. Shake.
“Building a robot!” Shake.
“Times up!” Clint yelled as the timer buzzed, and the Avengers groaned in defeat, rubbing their temples in exasperation.
“So…what was it?” Peter asked, curiosity bright in his wide eyes.
“Reading!” Thor exclaimed triumphantly, a wide smile plastered across his face.
Tony squinted at him, completely unamused. “What? That was not reading.”
“Yes it was!” Thor insisted, arms crossed proudly.
“No?” Tony grumbled, reaching down to pick up Mjolnir. “I don’t see it.”
Thor grabbed his hammer and sat back down on the couch next to Bruce, who had a calm, slightly tired expression and a yellow party hat perched crookedly on his head.
“I’ll go,” Tony slurred, standing unsteadily despite the floor already claiming him a few times this week. Peter watched him get to his feet, only to see Tony wobble and then collapse again with a soft thud. Peter sighed, pressing his hands to his face.
“Again?” Steve muttered, sounding more tired than worried, leaning against the back of the couch.
“Guess so,” Natasha shrugged, though her eyes betrayed that she had probably anticipated this outcome.
Peter crawled forward, gently rolling Tony onto his back and placing a hand on his forehead. His concern deepened when he noticed Tony’s slightly rapid heart rate, shallow breaths, and the faint flush on his cheeks, classic signs of a POTS flare-up after standing too long or exerting himself.
“Let’s just wait until he wakes up again,” Bruce said calmly, adjusting his glasses as he observed Tony’s vitals with a small scanner.
“Yep,” Clint agreed, sinking back onto the couch with the others.
After about a minute, Tony’s eyelids fluttered open. His gaze was unfocused at first, blankly scanning the room.
“What’s going on?” he mumbled, pressing the back of his hand to his forehead, his voice hoarse and tired.
“You passed out again, Mr. Stark,” Peter said softly, worry creeping into his tone. His eyes flicked to the slight paleness around Tony’s lips and the blue tinge in his fingertips, a subtle sign of oxygenation issues common with POTS.
“Told you to call me Tony, not Mr. Stark, kid,” Tony replied, barely caring about his collapse, brushing it off with his usual bravado.
“That’s all you care about?” Steve asked, his tone bordering on condescending, arms crossed over his chest.
“Shut up, Rogers,” Tony shot back, voice low but sharp, a faint smirk tugging at the corner of his lips.
-
5.
-
The lab was alive with controlled chaos, or at least, that’s what Tony liked to call it. Half-assembled suits cluttered the counters, wires snaked around prototype arc reactors, and monitors flickered with graphs and formulas that only Tony and Peter could decipher. Somewhere under a pile of tools, a faint hum pulsed from an experimental power source, like a heart beating just out of rhythm.
Peter perched on a stool near the edge of the workspace, notebook balanced on his knees, legs swinging anxiously. “So… uh… you’re sure this is safe?” he asked, voice pitched high with worry.
Tony waved a dismissive hand, tilting his head back with that trademark grin. “Safe? Kid, I practically invented the term. I mean, sure, we could explode a few things… maybe a wall… but nothing we can’t rebuild. And hey, it’s science. Science is… uh… messy. But controlled messy. Mostly.”
Peter didn’t look convinced. He’d seen “controlled messy” in Tony Stark labs before. Usually, it involved sparks flying, glass shattering, and Tony making a sarcastic quip before someone almost died. Today, Peter hoped that streak of luck would continue.
Thor, naturally, had to make an entrance at precisely the wrong time. Boots echoing against the lab floor, Mjolnir dragged behind him, and he stopped just short of the workstation, peering over Tony’s shoulder.
“Tony Stark,” Thor boomed, voice echoing under the high ceilings. “What… mortal sorcery is this? Green fire? Danger?”
Tony waved again. “Oh, don’t be dramatic. It’s… chemistry. Totally harmless, theoretically. Maybe slightly dangerous. Definitely fascinating. Science, Thor. Science!”
Thor’s brow furrowed. “Explosive science is not wise. I do not trust this green glow.”
Tony leaned casually against a counter, one hand fiddling with a glowing vial, the other tapping at a tablet. “Thor, where’s your sense of adventure? Where’s your flair for theatrical disasters that make you look heroic? If we survive, it’s cool. If we don’t… I go down in history as the genius who burned the lab down. Win-win.”
Peter squirmed in his seat, scribbling notes frantically. The moment Tony’s pulse ticked up, he felt the telltale creeping wooziness, the lightheadedness, the faint black spots at the edge of vision that meant trouble.
“Tony…” Peter started cautiously.
“Kid, relax. I’ve got this,” Tony said, trying to grin as he felt the familiar tightening in his chest and the slight wobble in his knees. “Minor… presyncope. Totally normal. Happens all the time. It’s called… uh… excitement.”
Peter’s notebook wobbled in his lap. “Excitement that makes you collapse?”
Tony waved him off. “Details. Not important.”
Thor leaned closer to the vial. “It glows like fire. I do not like this.”
“Great. More morale boosting,” Tony muttered under his breath, though his pulse was racing faster than it should. His vision darkened at the edges, but he refused to acknowledge it. Not here. Not now.
He added a pinch of glowing powder into the vial. Immediately, it fizzed and sparked, tiny green sparks shooting upward like miniature fireworks. Peter nearly toppled backward, notebook slipping.
“Whoa! That’s hotter than I expected,” Peter said, alarm rising.
Tony grinned shakily. “Expected? Kid, when have I ever done anything not hotter than expected?”
The sensation in his legs worsened, black spots multiplying, ears ringing faintly. The heat of the lab lights didn’t help. He swayed. Peter leapt to his feet, panic rising.
“Uh… Tony?” Peter said, voice sharp.
“I’m fine! Totally fine!” Tony said, fumbling to adjust a knob on the fume hood. “Just… physics. Excitement. Chemistry.”
Peter groaned. He had learned this particular combination of symptoms well: pulse racing, vision tunneling, legs unsteady. Only one thing followed: a collapse.
“Tony…” he said again, stepping closer.
“Minor… glitch in the Stark operating system,” Tony muttered, and then, knees buckled. The world tilted, black spots claiming his vision. He hit the floor with a thud, narrowly missing a precarious stack of arc reactors. Sparks flickered harmlessly from the vial.
“TONY!” Peter shouted, scrambling to his side.
Thor let out a dramatic shout. “The mortal Stark has fallen! By the Nine Realms, stabilize him!”
Natasha appeared as if by magic, crouching next to Tony, while Steve hovered, arms crossed but eyes sharp. Clint peeked in from the doorway.
Peter carefully propped Tony’s legs on a nearby stool, whispering, “Easy… just breathe. Stay calm.”
Tony groaned, his voice hoarse. “I… fine. Totally fine. Don’t… panic… minor glitch… science.”
“Science, huh?” Natasha murmured, raising a skeptical eyebrow.
Thor hovered dramatically. “Thou art truly fragile, Stark! Mortal weakness indeed!”
“Fragile is my brand,” Tony muttered, half-smiling, eyes still closed, still pale. “Makes the genius look better when I get back up.”
Minutes passed. Tony’s pulse slowed, color returned, and black spots faded. He lifted his head slowly, giving a crooked, exhausted grin.
“See?” Tony said, struggling to sit upright. “Totally fine. Nothing to see here. Just… chemistry. Science. Minor fainting. Standard Tuesday.”
Thor muttered under his breath. “Mortal body… treacherous.”
Tony snorted weakly. “Exactly. Mission accomplished.”
Peter let out a quiet sigh of relief. The secret remained safe. The Avengers still had no idea why Tony kept collapsing, and Tony was determined it would stay that way.
-
+1.
-
The Avengers had returned from a particularly messy mission in Berlin, an underground tech smuggling ring that had turned into an impromptu fireworks display thanks to Tony’s “improvements” on their gadgets. Everyone was tired, smelling faintly of smoke and takeout, and mentally drained from hours of chaotic coordination that somehow had worked out in the end.
Tony, of course, had refused to sit still. He strode into the common room in his slightly singed hoodie and sweatpants, muttering about mission inefficiencies and “people who can’t read schematics without tripping over their own feet.”
“Tony, maybe you should—” Natasha started, her voice sharp yet calm, her arms crossed. She had a habit of noticing the little things: the slight wobble in his step, the faint paleness under his usually tanned skin.
“I’m fine,” Tony interrupted, waving her off with a flourish of his hand that almost sent a half-empty cup of soda flying. “Just, just noting areas for improvement. Professional critique. Nothing to see here.”
Steve, leaning against the wall with his usual exasperated expression, raised an eyebrow. “You don’t look fine,” he said bluntly. “Since we got back, you’ve been… walking funny.”
“I’m walking like a genius, Captain,” Tony shot back, gesturing dramatically with both hands. “Genius Stark walking. Like a boss.” He attempted a flourish of a spin and nearly tripped over his own feet, his arms flailing like a bird learning to fly.
Peter, who had been hovering in the doorway with a stack of mission data and a slightly overstuffed backpack, immediately felt the familiar knot of worry tighten in his chest. He had seen this before: the way Tony’s color would drain, the trembling hands, the slight wobble in his knees before the inevitable thud on the floor. Only Pepper and he knew what was really happening, and it had always been a silent understanding between the three of them.
“Uh, Mr. Stark…” Peter started, stepping forward cautiously, “maybe you should… sit down for a sec?”
Before Peter could finish, Tony froze mid-step. His wide brown eyes darted across the room. His chest rose sharply, his knees seemed to forget they were supposed to hold him, and he stumbled toward the table, grabbing it for support.
“Whoa… whoa, okay,” he muttered, his voice strained but trying to maintain some shred of his usual sarcastic bravado. “I, uh…”
“Tony!” Clint shouted, immediately jumping from his chair. But it was too late. The world tilted sharply around Tony. Black spots appeared at the corners of his vision, his ears rang faintly, and a cold, creeping nausea made his stomach clench. His legs gave out entirely, and he collapsed, chest-first, onto the polished floor. A small, startled groan escaped him as he hit the ground.
Natasha was already crouched beside him, calm as ever but with a hint of exasperation. “Again?” she asked quietly, brushing a loose strand of hair from her face.
Steve crouched on the other side, scanning Tony’s form. “He’s pale… sweating… pulse is fast. FRIDAY, vitals?”
“Heart rate: 208 bpm. Blood pressure dropping. Oxygen saturation normal,” FRIDAY reported with her usual cheerful precision, completely at odds with the tension in the room.
Peter didn’t hesitate. He quickly moved closer and began carefully elevating Tony’s legs onto a chair, gently keeping them steady. He felt the faint tremor in Tony’s arms, the slight flutter in his chest, the little shiver of panic running through him despite Tony’s attempt at casual.
Steve’s eyes narrowed, a mix of worry and indignation. “This isn’t just ‘stupid Stark theatrics’ this time,” he muttered.
Peter took a deep breath, then said something he hadn’t dared say aloud before, knowing the room would react, but needing someone to break the tension: “He has POTS.”
The room froze. Clint’s eyes went wide, Steve’s jaw tightened, and Natasha’s brows shot up.
Peter continued, fumbling a bit but gaining confidence, “Postural… Orthostatic Tachycardia Syndrome. It’s, well, it’s why he keeps passing out. His heart rate spikes when he stands or moves too quickly, and his blood doesn’t circulate properly, so—”
Tony groaned from the floor, his voice weak but sharp: “Kid… that was supposed to stay a secret.” His usual bravado sounded oddly small and vulnerable as he leaned back against the chair Peter had propped under his legs.
“Secret?” Clint asked, sounding slightly scandalized. “So all the times we thought you were being dramatic—”
“I was dramatic,” Tony admitted immediately, “but not fake! There’s a difference, Barton!” He attempted a hand gesture, which ended up knocking over a stray soda can. Peter quickly caught it before it spilled. “See? Totally real-life chaos!”
Natasha shook her head, a small smirk tugging at the corner of her mouth. “Tony, why didn’t you tell us?”
Tony let out a sigh that was half exasperation, half embarrassment. “Because… look at you all. You’d hover, freak out, probably try to put me in a helmet or a straitjacket. Pepper and Peter help me survive this, fine. That’s enough.”
Bruce crouched down beside Tony, examining his pulse and posture. “You don’t have to hide it. POTS is manageable, especially with the precautions you already take. But you shouldn’t keep collapsing in front of everyone.”
Tony’s lips twitched, his usual smirk attempting to return. “I manage just fine. I’ve been managing for years. Pepper keeps the schedule. Peter keeps the snacks. That’s the dream team.”
Peter’s eyes softened, frustration and relief mixing in equal parts. “Mr. Stark… you almost gave us heart attacks multiple times. You can’t just shrug it off.”
“I know,” Tony admitted quietly. “And now… I guess it’s time you all know. Just don’t treat me like I’m sick or fragile. I’m still me.”
Steve’s stern expression softened. “We’re not gonna treat you like a patient. But we are going to help you, Stark. That’s what a team does.”
Thor, who had been quietly observing from the corner, finally stepped forward, Mjolnir resting against his shoulder. “Tony Stark… thou hast carried this burden alone for too long. From this day forth, thou shalt not endure it without aid. We shall act as guardians, allies, and friends.”
Tony gave a small, tired smile. “Thanks, Thunder God. I appreciate it.”
Natasha’s smirk deepened. “You’re ridiculous.”
Clint muttered under his breath, “All this time I thought you were faking it…”
“I wasn’t faking it!” Tony shot back, voice firm but a little playful, “Just surviving it… in style.”
Peter carefully helped Tony sit fully against the couch, letting him lean back comfortably. “You don’t have to survive it alone anymore,” Peter said, softly but firmly. “We can help you. We’ll make sure you don’t end up like this in the middle of a mission, or worse.”
Tony blinked, looking around at the team. The room was suddenly full of warmth, concern, and, surprisingly, humor. Steve and Natasha were still serious, but their eyes held understanding. Clint was muttering sarcastic remarks that still came out as affectionate. Thor looked ready to declare a ceremonial “protection vow” over him. Even Bruce, with his calm demeanor, had a tiny smile tugging at his lips.
“You all… really mean that?” Tony asked quietly, almost vulnerable.
“Yes,” Steve said.
“Yes,” Natasha echoed.
“Yes,” Clint added, though still muttering something about “the genius who faints.”
Thor simply nodded solemnly. “Aye. This burden is no longer solely thine.”
Tony sighed, leaning back into the couch, letting the weight of years of secrecy and embarrassment melt away just a little. “Fine. You know now. Don’t freak. Don’t hover. Just… be cool. Okay?”
Peter grinned, placing a reassuring hand on Tony’s knee. “We’ll be cool… promise.”
Tony let out a tired laugh. “Alright. Now… someone get me a drink. Preferably something sugary. And maybe a snack. For science, of course.”
The room relaxed in a way it hadn’t in a long time. The stress of the mission, the fainting, the secrecy, all of it softened under the weight of honesty and trust. Tony might still pass out, still struggle with his POTS, but he wouldn’t have to face it alone anymore. And for the first time in a long while, that felt… good.
Even Clint had to admit, under his breath, that it was kind of nice not having to jump in panic every time Tony looked slightly pale.
Natasha leaned back, arms crossed but smirking. “Just… try not to make a habit of it, Stark.”
Tony grinned, wiggling a finger like a tiny salute. “No promises, Romanoff. But I’ll try. For science.”
Peter rolled his eyes, shaking his head but smiling. “You’re impossible, you know that?”
“I know, kid. I know,” Tony replied, finally leaning back fully, sipping a soda as the rest of the team settled around him, talking, laughing, and teasing. For the first time in a long time, the room didn’t feel tense or precarious. It felt… like home.