Despite rushing into the living room and ripping Steve and me from our conversation and dragging us hastily to their lab, Bruce and Tony didn't feel the need to explain anything, apparently.

They dragged us in, told us to sit, and started conversing hastily about something, taking turns with a microscope.

I'd grabbed Stella on the way, and she now pounced around on the workbench, inspecting every little scrap of metal Tony and Bruce had lying around. I smiled fondly as she pawed at Dum-E, who was charging in the wall.

I was drawn back into the scene in front of me as Tony's and Bruce's voice grew louder, more excited.

"—but the blood cells have merged differently—look, it's—"

"Yeah, but that's not all, it looks like two completely different things up close—"

"—breakthrough like this could—"

"Uh, Bruce? Tony?" Steve said, standing without a clue in the world of what they were saying. "Wanna fill us in?"

Tony whirled around, seeming surprised that we were there. I raised my eyebrows expectantly.

"Uh, yeah," Tony said, grabbing some papers scattered around on the desk. "Yeah, just…when are the others due back?"

"I dunno," I said, getting a little impatient. "We'll tell them when they get back. Just…I want to know, okay?"

Bruce nodded, grabbing the papers out of Tony's hands. "Of course, Peter. Just…sit down, alright?"

Grabbing a stool, I sat. "Okay. Tell me. I'm sitting."

Tony took a deep breath and scrubbed a hand down his face, looking tired. Bruce didn't look much better. "We've been…comparing the data between you, and Steve and Bucky," Tony said, plucking a chart out of Bruce's hand and scanning it. "Mainly Steve, since he has the original serum. Mostly we've been looking at your bloodwork, but also at your vitals in response to exertion and physical strain, and…well, the qualitative data was very similar. You definitely have some kind of serum in your blood, but…it's definitely not the same as Steve and Bucky's."

Silence.

"Wait…what?" Steve asked, looking perplexed. I couldn't speak I was so shocked. "I thought that was the whole point of his parents injecting him. They rediscovered the super soldier serum and injected him to—well, allegedly, to keep it safe. That's what their research was on, mainly."

"You're right," Bruce interrupted, looking at me apologetically. "But that's not what we found in Peter's blood. It…has incredibly similar effects, but…it's distinctly not your serum."

"Then…" My voice broke, and I cleared it, shocked. "Then…what is it?"

Tony and Bruce glanced each other before Tony sighed. "We…we don't know, Pete."

"So…it's not Bucky and Steve's," I said numbly, staring at the microscope. "Then…what…what is it? Bruce, what's inside me?" My breaths became shallow as my heart sped up, and I gripped the edge of the stool. "What did—what did they put in me—Tony, I—"

"Peter? Peter, look at me," Steve said, voice worried. "Peter, you're panicking, okay? We've been through this, you need to calm down. Remember what Bucky said?" I tried to nod, but I just ended up gasping, darkness creeping in the edges of my vision. "You've gotta find some sort of anchor. You're here, okay? You're safe."

"I'm—not," I gasped, feeling frustrated tears leak out of my eyes. "Not—sa—safe—"

Steve's eyebrows drew together. "Okay, why aren't you safe?"

"It's—" I panted, my head growing airy and light, hyperventilation starting to take its toll. "In… side—" I put a hand on my chest, like I could show him through a window that something was physically inside of me.

Bruce and Tony stood back, watching worriedly. Tony had his mouth open, like he wanted to say something, but with a glance at Steve he backed up, watching with worried eyes. Bruce had his lips pressed in a thin line, eyes tainted green, hands gripping the workbench as he took deep breaths.

Oh. Maybe I should take deep breaths. When I tried, though, I couldn't. My lungs wouldn't expand properly.

Stella had stopped messing with Dum-E and had come over to me, standing on her back legs, pawing at my legs and the stool legs, meowing worriedly. I wanted to scoop her up, hold her, let her cheer me up, but I could barely move. I couldn't breathe. The panic was settling in now, into my bones, my flesh, my blood, just like—

"Ste—" I gasped, breaths ragged. "Steve—"

"I get it," he said, voice low, smooth. His hands tightened on my shoulders, holding me steady. "I get it. Remember? I said I was a sickly kid, right? I had asthma. Not quite as bad as a panic attack, but…it feels the same in some ways. Wanna hear a trick I used to take deep breaths? Yeah?"

I nodded, still wheezing in breaths, hands grasping his wrists desperately. He continued, "Okay. This is New York, and you've lived here your whole life. You must know a lot of streets, huh? Not all the numbered ones, like First Street. The good ones. C'mon, tell me as many as you can, okay? Think of all those streets."

"Br—" I gasped, trying to calm my mind, choking on the word. "Broad…way—"

"Broadway, good," Steve said, clenching my shoulders.

"Green…" I huffed, my chest expanding rapidly as I inhaled. "Street…"

"Green Street," he nodded, looking serious. "Can you give me one in Queens?

I thought furiously, then I remembered where May and Ben and I used to go. We would take walks up and down the cobblestone, stopping for ice cream and taking pictures in front of our favorite shops. I'm sure I still had a picture somewhere in our old house.

"Ast—" I forced myself to exhale roughly, then sucked in a deep breath—still quickly, but I felt the lightheaded feeling lessen slightly. "Astoria…Boulevard."

"There we go, kiddo," Steve said, relief evident on his face as my breaths became smoother, slower. "There we go. Deep breaths, that's it."

"Hey, FRIDAY said you guys were in he—Peter?" Rhodey's voice echoed as he came into the lab, his braces back in place after his physical therapy session. "What happened?"

"It's okay," Steve said as Rhodey hurried over, hand on my shoulder as he looked between us. "He had a small panic attack, but we got it under control. You did really well, Peter."

I nodded, still focusing on taking deep breaths, but I squeezed Rhodey's wrist to let him know I was okay. "Sorry," I breathed, feeling my cheeks heat up.

"No reason to be sorry, kid," Rhodey said, clapping me gently on the shoulder, turning to Bruce and Tony. "What happened?"

"We, ah…" Tony said, rubbing the back of his neck. "We found out that the super soldier serum—Steve's and Bucky's—isn't what Pete's parents injected him with."

Rhodey blinked, looking as surprised as the rest of them. "What? Then how…?"

"It's something else entirely," Bruce said, eyeing me warily.

I took a deep breath and nodded, relishing Steve's comforting hand on my shoulder, though I kind of wanted Bucky. But I wanted to know now. I wanted to know everything I could. "It's okay."

"Well," Bruce said, "we tried to…kind of guess what your parents were working on. You told us they were comparing the serum to different cross-species genetics, so we did some digging around into successful research in that area, but it's very limited. Very few breeds have ever made it past the first couple of experimental stages, let alone gotten approval for testing."

Tony tapped his StarkPad, throwing a holographic diagram of three double helixes onto the wall behind us. I watched, fascinated, as the holograms warped and shifted. "The one on the left is a sample of my blood, one hundred percent human, for reference. The one in the middle is Steve's."

I looked closely at Tony's, and then my eyes shifted to Steve. I could tell immediately, even with my very limited knowledge of anatomy, that something was obviously different. "What is that…?"

"Good eye, Pete," Tony said, zooming in on just his and Steve's, putting them side by side. "So, a double helix is effectively a piece of DNA. The two strands are connected by Hydrogen bonds, in the form of nucleic acids—A, C, T, G. Put them in the right order, and you're basically giving your body instructions on how to perform basic functions. See mine? Completely normal. On Cap's, though, you've got some big differences."

He zoomed in on Steve's double helix, and the disturbances became clearer. "There are…bumps?"

"Not quite bumps," Bruce said, enlarging a singular rung on the nucleic acid ladder. "More like spores. The molecules of the serum he was injected with all those years ago has dispersed throughout his entire body, seeping into his DNA and bonding with his nucleic acids. Like Tony said, each strand gives your body instructions—how much to eat, how fast you heal, the chemicals you secrete in certain situations…that's why Steve is enhanced. The spores are literally enhancing his DNA right down at the source, making it superior to a normal human's."

Tony threw the diagram of Steve's and his DNA into the back, and I sat forward, anxious to see where I stood in all this. "So…what? You said I don't have the same serum as Steve and Bucky, but is the serum they injected me with like that? Do I have…spores…on the DNA all over my body?"

I chanced a look at Steve, to gauge his reaction to finding out he had chemical mushrooms growing all over his body that were practically invisible, to find him looking distinctly ill.

Yeah. Me too, Steve.

"No," Bruce said, tapping the final helix, enlarging it on the screen. "This is yours, Peter."

And suddenly, I wanted the mushrooms.

"What am I looking at?" I asked, my voice trembling. I slid off the stool and approached the wall wide-eyed, gingerly touching the holographic display. "This…can't be mine. It's…I don't understand…"

"It's yours, Peter," Tony sighed, sounding grim. "We checked to be sure it wasn't contaminated. Three times. And…this is what we got."

I turned to Bruce and Tony, eyes wide, uncomprehending. I liked science. I loved science. But…when I thought about all the scientific reasons for this, all the possibilities, it…it was terrifying. "But…what is it?"

"Well," Tony said, sighing, rubbing his neck. "We're still guessing. I've got FRIDAY running a program now, checking your DNA for similarities against successful diagrams of cross-species genetics in every top-name STEM corporation there is, but it's a slow process. Here's what we do know."

My DNA was…warped. He zoomed in even further, to a singular rung, just like he had Steve's. There were no mushrooms. Instead, parts of the helix were…broken, almost, but…together? It was like a broken bone that had grown back misaligned. This…was what composed my body. These broken strands of DNA. I suddenly felt like a house of cards in a windstorm, ready to topple at any moment, seeing the building blocks of my entire being so…misshapen.

"You have some kind or foreign DNA in your body," Bruce said, taking over for Tony. "The reason it looks haphazard is because when you were very young—we assume when your parents gave you the serum—your DNA literally broke itself apart in order to bond with the foreign substance. I assume you don't remember being injected?"

"N-no," I said, transfixed by the diagram in front of me. "I mean, I think it was…right before they dropped me off at May and Ben's. That would make…the most sense, right?"

"Did you feel sick? When they dropped you at your aunt and uncle's, and for a few days after?" Tony asked, glancing up from his screen.

"Yeah, actually," I said, confused as to how they knew that. "I…I was running a really bad fever and in a lot of pain, all over. It got really bad after I got the news about my parents, so all of the doctors and child psychologists told us it was…a form of shock, I guess. That I was…let me remember…I was 'manifesting my psychological pain to make it easier to deal with,' or something like that." I glanced back at the screen. "But…that wasn't it, was it?"

"Unfortunately, no," Bruce said, and I felt Steve squeeze my shoulder reassuringly while Rhodey paced and Stella rubbed her head into my chest. "That was your body trying to bond with the foreign substance and keep it from killing you."

"Oh," I said shakily.

"Luckily, you bonded with it successfully, and it's been growing with you, adapting to the changes your body is naturally going through. It was probably only possible because you were so young, and your body was able to adapt quickly." Bruce continued. Tony was typing furiously, looking at several other diagrams, laser focused. "So, instead of Steve's, where the spores on his DNA are enhancing his natural processes—speed, strength, healing, etc.—yours are just…completely different."

"But…" I started, unsure of where this was going. I was the opposite of Steve when it came to physicality. I wasn't fast, I wasn't strong. I healed a little quicker than normal, but nowhere near his level. "I don't understand. I'm not very…enhanced…?"

"We've got a theory on that," Tony piped up from the computer. "We think Cap's physicality was enhanced immediately because he was already an adult when he was given the serum, so all it had to do was take the abilities he already had and…improve them. With you, you were still a little kid, nowhere near your full potential. Bruce and I think that the foreign DNA had to adapt to all of the changes your body has been going through, so it literally hasn't had time to enhance most of your physical abilities yet. Now, the abilities you have will probably depend on the type of foreign DNA in your body. Animals have all different kinds of evolutionary techniques. Who knows, you might grow a tail." At my very unamused look, he coughed a laugh.

"But," Bruce said, shooting Tony a look, "we think we've found the cause of your dizzy spells."

I perked up. May and Ben had taken me a doctor when the spells started getting bad, just after I turned seven, but she never gave us a definite diagnosis. Having just taken me in, it wasn't like they had money to spare, so we had to just accept it and deal with them as they came. "Really? What is it?"

"Well," Tony said, rubbing the back of his neck. "It's…actually really boring." He glanced at Bruce, who nodded, and sighed. "It's just…your metabolism, kiddo. The foreign DNA in your system apparently requires a lot more nutrients to sustain all your natural functions than the average teenage boy does. Since you've just started eating what was considered normal for others your age and body type, and even before then not eating enough…well, it's no wonder you'd get dizzy so often."

Metabolism.

My metabolism.

"You're telling me," I said, leaning forward, probably looking absolutely incredulous, "that I've been getting dizzy my entire life because I wasn't eating enough? Like, ever?"

"Nope." Tony said, looking back at the screen. "You didn't get them before you were six, did you?"

"No," I admitted, feeling my hands shiver.

"So. It's the foreign DNA messing with your body." Bruce said, cutting Tony off before he could open his mouth again. Tony pouted. "It's also why you heal a little faster than average. Your rate of healing and metabolism are fairly constant throughout your life, so the first enhancements took place at the very beginning. We think your full potential of powers will start to develop when you get further along into adulthood. It could come out before then, but…it would be something like severe trauma to your entire body. I suppose it would come out as a sort of…defense mechanism, then."

I ignored most of that in favor of thinking very deeply about what had just been said.

I was enhanced.

With foreign DNA.

Most likely animal.

"Oh, God," I breathed, pressing a hand to my mouth, feeling my stomach flip. "I'm not gonna, like, turn into a werewolf or anything, right?"

Rhodey snorted suddenly into his hand, and Steve blinked in surprise. Tony and Bruce shared an amused look at my unsuspected comment. "No, Pete, you're not," Tony said with a cocky grin. "That was funny, though."

"Not to me," I huffed, looking back to the screen. "It was a legitimate concern."

Suddenly, FRIDAY's voice came over the speakers. "Boss, the others are back. Should I send them to the lab?"

Four pairs of eyes turned to me with questioning looks, and I sighed dejectedly, thinking of how well Bucky was going to take this. "Might as well."

…

Bucky didn't take it well.

He did that thing he does when he's really mad. He ruffled my hair, got this thousand-yard-stare in his eyes, and walked away, disappearing for the next several hours without a word.

And if there were six destroyed punching bags the next time I stepped in the gym…well, crazy stuff happens in Avengers Compound all the time.

The others didn't take it very well, either. Tasha did, since she was, ya know, a superspy. Clint was pissed, which I could understand, since he was a dad himself. That's not something you do to your kids, under any circumstances. Thor was…understandably upset, but instead of going all god-of-thunder-and-lightning-raging-battle-mode, he sort of…sulked. He stole Stella for a while and took her outside to play around. I guess she made him feel better. Sam wasn't too happy either, and went to stress bake.

And if the entire pan of brownies was gone after my next trip to the kitchen…well, like I said—just another mystery.

I slunk to my room not long after we told them and stayed holed up in there the rest of the day, trying desperately to process everything.

"FRIDAY," I said to the ceiling, folding my hands behind my head and laying back on my bed, closing my eyes. "I don't know how to deal with this."

"If you'd like, I could compile a few helpful books on dealing with emotional or psychological trauma." She said, her voice low and soothing. "You may find them helpful in terms of overcoming your initial fear or apprehension."

I rolled over onto my side with a sigh, missing Stella's warmth. I didn't want to take her from Thor, though. "No, that's okay. I just…it's just a lot to process, you know?"

"Actually, I have the ability to process trillions of bytes of information per second, so I'm afraid I cannot identify with your feeling." She replied, straight and to the point.

I put on my most unamused bitch face and looked at the ceiling.

"Your expression indicates that you are unhappy with my response."

"Well, at least your powers of observation are still intact," I huffed, getting up and stretching. "I'm going to take a shower."

"Alright, Peter."

I didn't get to take a shower, though, because Clint dropped out of the vents and landed two inches from me, a grin on his face.

I jumped. I mean, I literally freaking leapt at least four feet in the air trying to get away. When I realized it was him, I panted, putting a hand to my chest and yelling, "Why is one of your primary hobbies scaring the piss out of me?"

"Aw, don't be mad," he chuckled, cackling at my reaction. "I need some of that brainpower."

"You could have used the door!" I shouted, trudging to my bed and sitting down before the adrenaline crash took my legs out from under me.

"Geez, you're a stick in the mud, today. Cap's rubbing off on you." He grabbed my forearm and tugged me out the door—thank God, not the vents—and down the hallway. "Come on. To my fortress of solitude. I need your help."

"With what?" I huffed, shoving the hair out of my face, prying my arm from his grasp.

He turned around and put on a thousand watt smile only challenged by the resident billionaire. "Getting back at Tony Stark, of course." At my confused blink, he grinned even wider. "Welcome, Peter, to your first official Avengers Prank War."

A/N: So, some big revelations here today! I kind of took some creative license with the DNA stuff, but I tried to make it as scientific and believable as possible, and I did a bit of research, so I hope it was convincing! But yeah, so they're on their way to figuring out what EXACTLY is wrong with Peter.

Okay, I know I promised you more bonding in this chapter with more Avengers, and I'm really sorry, but that's not how it played out, you know? This just seemed like a good place to cut it, since it was getting a little lengthy anyways, and writing all the angst kind of wore me down a bit, too. Next time! I promise!

Yay! Peter gets to have his first prank war! Unfortunately, I've planned nothing past this. Like, I have the rest of the story planned out, but as far as the specifics for the next chapter, I've got nothing. All I know is that there will be a prank war, and if it's possible, it will be epic. If you've got some good pranking ideas, feel free to drop a review, and I'll probably use them, because I suck at pranks!

Huge shoutout to all my beautiful wonderful reviewers for Chapter 20: Ammy of Asgard, PrincessNaina, SkyDreamer12, Melancholy's Sunshine, Spawn Hades, Winter spider, starr1095, AndurilofTolkien, BabyPinkPuppy, GoddessOfFanfictonn, spidermanpls, RosettaQueen20, The Striking Storms, TC Howl, CelinaB, monkeybaby, Andipandi5, kittymyth96, , DemonSkitty, katwinchester, Caraline Fisher, ALonesomeAuthor, OneOfYourFans, Diva, Lydywritesactually, , the Guest, TheKingOfTheMotorMouth's, Esha Napoleon, and CaptainDingbat! I really appreciate you guys! Also, I've gotten quite a few more follows and favorites recently, and the surge in support has been so heart-warming! Thank you so much!

OneOfYourFans: Haha yeah, I posted a little earlier in the day than I usually do, I think. I know Bruce is so sweet T-T don't worry, more bonding to come! Also…have you learned nothing? ;)

Diva: Awww thank you so much! I really appreciate! Don't worry, not planning to stop writing anytime soon :) Hope you liked this chapter as well!

Next: that bonding that never happened that I promised you…plus a prank war ;) See you next Saturday!