This is it, The Apocalypse

Chapter One: Hulk

Tony Stark had a multitude of shortcomings. He was egotistical, prone to self-destruction, possessed an incredible ability to bottle everything up until circumstances became so dire that he was quite literally dying. Yet despite all these, his inability to trust, however justifiable, had become the true burden, one that weighed so heavily on his soul that he could feel it physically. He recognized it as clearly as he could the face of an old enemy, so no matter how much he vehemently attempted to ignore it, it would be there regardless, in the back of his mind, paranoia and instant distrust dominating any and all first impressions.

So when he'd placed his life in the hands of five complete strangers during the attack on Manhattan, he'd seen this act as an extreme step in the right direction and he'd figured, eh, why not take a couple more steps and offer Dr. Bruce Banner a home? In all reality, Tony had needed the company. Pepper's presence in his life was a wonderful, grounding distraction but she happened to be a very busy person and spent most days either away on business or on the phone, as she attempted to mitigate the unfavorable media attention Stark Industries almost constantly received nowadays. She was also no scientist, and Tony had found himself immensely enjoying the presence of another human being capable of not only following his scientific meanderings but improving on them. It was exhilarating, bouncing theories and ideas back and forth between him and Bruce, and amazing technological and medical breakthroughs were becoming more commonplace than ever before.

Who did he think he was kidding? Bruce Banner was quite possibly one of the most trust-worthy individuals in existence, ranking alongside Gandhi and Jesus. Tony's sort of self-designated trust test, in which Bruce had been the unwitting subject, had been absolutely shamtastic in it's essence. Sure, Bruce had this slightly annoying little disability that caused him to turn large and green and unpredictable, but Tony was ok with that. In fact, as ironic as it was, he considered the Hulk just one more of the many attributes that made Bruce so incredibly genuine.

So one day, when Bruce inquired into the specifics of his Arc Reactor, something Tony had shared with virtually no one, there was only a moment's hesitation before he had decided he was perfectly ok with it.

"Here, check this out." Tony hopped onto a table and lifted his shirt contentedly, allowing a curious yet reserved Bruce Banner to inspect the Arc, it's serene blue glow revealing age and scars on the other man's face as he leaned in to observe it. "You already understand how my big reactors work so just think of this as a compressed version, small enough to fit snugly into one's sternum."

"It's incredible." Bruce stated, running fingers lightly over it's shining surface. "And you said the arc powers an electromagnet embedded in the socket casing which ensures the shrapnel remains stationary, correct?"

"Partially correct." Tony placed his fingertips around the outside of the device and located the tiny release button, pushing it, and twisting the arc within it's socket with only the slightest hitch of his breath. It was still painful to mess with this thing. He removed it from it's housing slowly, careful not to yank the device completely out. Bruce displayed an expression of minor concern, but did not voice it, obviously confident in Tony's ability to judge when enough was enough. "You see those wires leading down from the arc to the base plate? It also powers a complex pacemaker. Keeps my ticker running relatively normal, considering."

Bruce peered inside the socket and frowned. "Tony, this is an enormous cavity. Whoever did this must have removed vital pieces of anatomy just to make it fit. A substantial amount of your sternum -"

"A couple ribs, pieces of my lungs, yeah. He dug in pretty deep. Altered the entire physical makeup of my torso." Tony hadn't meant to cut Bruce off but thinking of Yinsen, and his heroic surgical proceedings was painful. Discomfort made Tony act inappropriately and this was no exception.

Bruce maintained his disapproving frown as he peeled his eyes away from the horrific socket to look up at Tony. "Can I feel around in there a little? I just want to gauge how big it is."

Tony regarded him with faux skepticism. "Well honestly doctor, I'd like to see your credentials before you go probing around inside me."

"Oh, save it, Stark." Bruce said, smiling and obliged himself to gently prodding the socket wall. His smile faded once more only to be replaced by a deep concern that furrowed his brow. Tony was beginning to regret this. He did not want Banner stressing over something that was done and over with. "This causes you pain, doesn't it?"

It wasn't a question. Bruce knew damn well that there was no way the invasive implant didn't cause him pain and Tony sighed, realizing there was no lying to this man as he had done with so many others. "It's...uh... uncomfortable, yes. But I'm used to it. Like I said way back when; it's a part of me now, discomfort and all."

Bruce removed his fingers and Tony replaced the arc with a series of clicks. "There's no way the natural rise and fall of your diaphragm doesn't cause it to rub against your ribs."

"Remind me to give you a cookie later for that acute observation." Tony quipped with a peaceful smile, pulling his shirt back down and pushing himself off the table. "Since we're all up in each other's personal secrets, I have a question about you."

"Tony, I'm still concerned with the chronic pain you must experience. As a doctor, I can't just sit back-"

"I want to know what it feels like to go Hulk."

Bruce visibly bristled, and Tony wondered for a moment whether or not this topic was off limits. He watched the doctor with fierce anticipation, regretting the question only slightly but still curious enough to keep himself from withdrawing it. After avoiding Tony's expectant gaze awkwardly for a minute or so, Bruce finally seemed to relent, sighing and removing his glasses to rub the bridge of his nose. "It's, uh... it's extremely complicated."

"So when you get really pissed off, do you see green instead of red like normal people?" Tony deadpanned, determined not to let the doctor wiggle his way out of this one.

Bruce emitted a sardonic chuckle and collapsed into a chair. "Not exactly. I don't necessarily black out anymore, unless I lose control of him."

"So how does it feel then? When you lose control?" Tony sat as well, resting his chin on his fist.

"It's terrifying," Bruce said, maintaining a steady gaze on the floor. "It always happens when extreme, unexpected events occur. When the Other Guy feels that I'm in danger, or that I'm losing control of my anger he forces himself through... to protect me. Imagine a perfect storm of fear, anger and hysteria. All these emotions occur simultaneously and then, the, uh... the pain starts."

"Rapid unchecked expansion of muscle and tissue," Tony elaborated, eyebrows raised, a small comforting smile gracing his features. "I don't know why you're so concerned about me, Dr. Banner, that sounds a hell of a lot worse than a little rib friction."

Smiling sheepishly, Bruce sighed and massaged his temples. "Yeah, it's certainly unpleasant."

"You always refer to Hulk as the 'Other Guy'. Like he's a being completely separate from yourself." Curiosity was something Tony could not tolerate, and he wanted answers while Bruce felt like opening up, hesitant or otherwise.

"He is. Complete with his own set of likes, dislikes and opinions. Admittedly skewered opinions but opinions nonetheless." Suddenly, he looked up, meeting Tony's gaze, his smile vanishing and his eyes troubled and glossy. The sudden change in demeanor startled the billionaire. "Tony, I don't think I can do this," He said, a small, restrained hint of desperation accompanying his words.

Baffled, Tony watched him as he ran frustrated hands through his already mussed hair. He had a feeling this unexpected angst did not originate from his prying questions, but experienced a pang of guilt all the same. "Forgive me for being blunt but, where the hell did that come from?"

"Don't you get it, Stark?" Bruce snapped, his eyes flashing emerald and Tony felt fear of this man for the very first time. He had never been the direct target of Bruce's anger before and understanding exactly what lurked beneath the normally peaceful exterior made the experience all the more humbling. "I should be staying as far away from stress and violence as possible, not gallivanting around with five people who happen to draw in chaos as though they possess gravitational pulls for it! I've got another... thing inside of me that I have little control over, who reacts directly to chaos, who feeds off chaos, and I'm expected to be a valid member of a team?"

The doctor was breathing rather hard, clenching his fists impulsively, and Tony put his hands up in an attempt to placate this unexpected outburst. "Ok, first I think you need to take a couple of deep breaths," he suggested, keeping his fear hidden behind a mask of stern confidence. Bruce remained exasperated for a full five minutes before he was able to rein in his anger, stuffing it away in whichever dark corner of his mind was large enough to contain such a burden.

He glanced up to note Tony's worried expression and sighed, lowering his eyes once more in shame. "I'm sorry, Tony." The simple apology was more than sufficient.

"So... you want to tell me what's up?"

Bruce slowly closed his weary eyes and rested his face in his hands, obviously conflicted. "Remember when Clint attacked the heli-carrier, and I ended up trapped beneath the lab with Natasha?"

Tony nodded, worried that he knew where this was headed. His heart was still pounding from Bruce's outburst and he had to concentrate on all his individual muscles to keep his limbs from visibly quivering.

"Well, I found out later what happened, and I've been mulling it over a lot. The Other Guy... he nearly killed her. And Thor, and just about everyone else on that ship. All because of a little explosion." He opened his eyes once more to meet Tony's neutral stare. Bruce's guarded expression saddened him but he contained his own emotion, resolute on remaining the beacon of stoicism the physicist felt he could rely on. "I'm a liability to the safety of the team, Tony. I'd be an idiot if I expected to completely avoid all life-threatening situations while involved in such an extreme organization. I can't participate in missions if I'm going to lose myself to every little boom."

Tony felt a smile spreading across his face as the fear and anxiety began to dissipate. He couldn't help it, really. It was all timed so perfectly. When he noticed the hurt and utterly stricken look Bruce shot him, he quickly collected himself. "What if I told you that I've been working on something that could make a majority of this problem disappear?" Ignoring Bruce's perplexed stare, he sprang up from his chair and walked quickly over to a cabinet, retrieving a large, sealed cylinder containing a bright blue liquid. He handed it over to Bruce, grinning like a maniac.

Turning it over in his hands, and finding no label, Bruce looked back up at Tony skeptically. "What is this?"

"That, my friend, is Hulk-Off. Clinically proven to temporarily eliminate 99.99% of all Hulk-related side effects including, but not limited to greenish skin, muscle enlargement, gigantism, rage-induced violence, nakedness and obsessive smashing." He beamed proudly as the ghost of a smile began to tug at the corners of the other man's mouth. "Theoretically it should reverse any unintended transformation as long as you aren't already fully Hulked-Out. Right now, if my formula is correct, it will only work when you are in-between you and Hulk."

Bruce peered into the blue contents longingly, unidentifiable emotions flashing across his face. "You know," He finally whispered, "I've been wanting to create something like this for a very long time. I just never had the lab or the resources... or the geographical stability to do so."

Tony's smile grew and he patted Bruce on the back. "Hey, I'm here for you. So no more of this worrying business, alright? I got you." He waved his hand in the air and a screen appeared. "JARVIS, bring up file Hotel, Oscar, Whiskey, six, two, nine."

"Right away, sir," came the smooth British voice from seemingly nowhere. "Accessing classified file, Hotel, Oscar, Whiskey, six, two, nine."

Almost immediately images began appearing on the screen before them, containing what looked like weapons specifications. Bruce placed the serum on the table next to him and stood to view the file. "Are these-?"

"-all the ways in which every member of the team can administer this serum based on their individual skill set at any given moment?" Tony interrupted, flipping through the data. "They are indeed. Check this shit out. I've designed non-lethal hollow ammunition for Natasha's pistols, tracking darts for myself, serum infused arrow heads for the Hawk... um, honestly I'm still working out what to give Cap and Thor without freaking them out-"

"Tony, this is amazing." Tony ceased rattling off information to take notice of the way Bruce's voice wavered when he spoke. Surprised, he glanced over at the doctor, and was relieved to see no tears. Instead, a gratuitous smile had pushed it's way in among the wrinkles and stress and pain as he inspected the renderings. "No one's ever done anything like this for me before."

"Well that's what happens when you're friends with Tony Stark. You receive well deserved gifts for managing to deal with my bullshit on a near-daily basis."

"Thank you."

Tony looked Bruce in the eyes, elated to see the last ounces of his previous anxiety melting away to reveal content, like frost off a window after a long, long winter. "No need to thank me. I'll be damned before we lose our Hulk. I'm pretty sure I watch the security footage of you slamming Loki around like a dirty rug no less than twice a day."

Bruce laughed, a genuine, hearty laugh.

A/N: Ok, so initially I had intended this to be a one shot. Crazy, right? Well I kinda got caught up in the interaction between Bruce and Tony and, upon realizing that just this one situation was becoming very lengthy and elaborate, decided to make it a short series, about 6 chapters long. This is basically a test fic, in which I attempt to write all the Avengers as in-character as possible and see how I do. I'm gonna need a lot of help on this one guys so reviews are very, very much appreciated. Please let me know if I screw up anyone's character via constructive criticism. Next chapter, prepare for a little bit of Clint angst. Good times shall be had by all!