Here we are! The beginning of the end for Changing of the Guard. This final arc will be the craziest thing I've done in this series yet - so please, be patient with me. It takes a lot of behind-the-scenes planning and work for this to happen, so the next few updates might be a little slow. This is the first crossover between any two fics of mine - specifically, with The Girl Who Could Knock Out the Hulk - so while I hope you're at least somewhat familiar with the backbone of this entire series, I have to make sure those of you who aren't into that fic can still understand what's going on here.

I'm shooting for about 5 more chapters in this fic, so there's still quite a bit of writing to be done! I hope you enjoy it.

"Benjamin Kirby Tennyson." -the S.H.I.E.L.D. agent begins reading from a folder containing his dossier. "Only child of Carl Tennyson, former campaign manager and current Chief of Staff for your mother, US Representative Sandra Tennyson."

Ben raises an eyebrow. "Most people would mention my mother first. Both of my parents included."

Coulson raises an eyebrow, but doesn't comment. "A spotless criminal record, middling to slightly better-than-average grades, minor ADHD tendencies...mostly raised alongside Kevin Levin by your grandfather, Maxwell Tennyson, due to your parents' responsibilities on Capitol Hill." -he continues, then smiles. "How is Max doing, these days?"

Ben scowls as honestly as he can manage. "He's...not doing much. I guess you didn't hear, but...he's dead, sir."

"You and I both know that's not true, Mr. Tennyson." -Coulson says. "It took a while, but the final casualty report for the Battle of New York finally came in a week ago - all deaths, injuries, and missing persons accounted for. Seventy-four people lost their lives to the Chitauri that day, and your grandfather was definitely not among them." -he explains, narrowing his eyes.

"In fact, he never made it to New York to begin with. I can't be sure, but it might have something to do with the fact that his video, cellphone, and satellite trail goes cold in Nevada, and radar pings in the area indicate a small, unidentified aircraft breaking atmosphere at speeds that would make Tony Stark jealous."

Ben winces. That sounds exactly like Grandpa Max leaving on his quest to rejoin the Plumbers. He wonders if Area 51 is secretly owned by S.W.O.R.D., or something to that effect.

"Besides, this is Max Tennyson we're talking about. He'll probably outlive us all." -Coulson smirks.

"How do you know Grandpa Max?" -Ben asks, unable to resist his curiosity. "He never mentioned knowing a S.H.I.E.L.D. agent."

"I'm sure there's quite a bit about Max you - or any of us, for that matter - don't know. Judging by the extraterrestrial timepiece on your wrist, and their current attempts at breaking their usual radio silence, I assume you've been in contact with S.W.O.R.D.?" -he asks, though it doesn't really sound like a question. Leave it to a secret agent to act like he knows everything there is to know.

"What do you mean, 'extraterrestrial'?" -he feigns ignorance and surprise. Poorly, given the agent's reaction.

Coulson purses his lips, like he's heard something like this many, many times. "Let's not do this, Mr. Tennyson. We've only been here half a day and we've already gathered enough evidence of extraterrestrial contact to warrant an indefinite lockdown of Arcadia. We have fairly reliable footage of several distinctly non-human entities bearing an emblem identical to the one on that device." -he explains, pointing at the Omnitrix. "Not to mention, the minute you walked into our complex, the machine on your wrist set off all sorts of alerts regarding the presence of exotic metamaterials - the kind you can't find or even make on Earth."

Ben sighs. "I mean, you seem to know everything, agent Coulson. I don't know what you even want me for."

"I don't know everything." -he admits. "I don't know what your relation to these creatures is. I don't know what their intentions are. And I certainly don't know how half a dozen teenagers of seemingly Enhanced status and what appears to be their underground lair escaped S.H.I.E.L.D.'s notice."

Coulson leans forward. "S.H.I.E.L.D. doesn't like unknowns. We can't protect people if we don't know what to expect. Your grandfather understood that - that's why he joined S.W.O.R.D., and why he consulted with S.H.I.E.L.D. on certain superhuman matters. That's how I know Max Tennyson." -he says. "And it's why I'm hoping you can help us figure out what we're dealing with."

"What we're dealing with, you mean." -Julie says, scornful. "Last I checked, the only people protecting this town were us."

"You're right, Miss Yamamoto." -Agent Coulson admits. "The evidence we've gathered so far points to several weeks of activity, enough time that we should've noticed what's been going on in Arcadia ten times over, aftermath of the Chitauri invasion notwithstanding. As it stands, we still aren't sure of what you've been protecting Arcadia from. Maybe you'd like to illuminate us?"

Julie crosses her arms. She doesn't know much about S.H.I.E.L.D. - nothing beyond what little they've told the public following New York, really - but their rather aggressive entrance tells her she shouldn't trust them. "Ask Abigail Brand." -she says, sardonic.

"S.W.O.R.D.'s existence isn't public knowledge, let alone the name of its Director." -Coulson notes. "Even S.H.I.E.L.D. is only tangentially aware of their activities and vice versa - just enough that we don't get in each other's way. Left hand doesn't know what the right hand does, and so on." -he muses.

"Sounds to me like a recipe for failing to stop alien invasions." -Julie sneers. "Without lots of help from an assorted bunch of superheroes, at least."

Coulson raises an eyebrow. "I actually agree with you. It would be much more efficient for all of us to work together - S.W.O.R.D., S.H.I.E.L.D., and any remarkable individuals willing to lend a hand, such as the Avengers. Such as you, apparently."

"I don't have any powers." -she says, almost reflexively.

"But you do have quite a bit of advanced gear on you. Damaged, maybe, but still beyond anything even our operatives are currently fielding." -Coulson says. "...and that's without even mentioning your arm."

Julie shrinks into herself. "...w-what about it?"

Coulson's expression softens. "Well, for one thing, its holographic camouflage is clipping." -he nods at her.

She looks down, and indeed, part of the hologram that conceals her Kree prosthetic has phased into her human arm. Julie curses. "I've examined your file rather closely. You seem to be somewhat injury prone - an unfortunate side effect of your extensive career in various sports, and, I'd assume, what your psych eval charitably describes as a competitive streak." -he says. "But this is something else entirely, isn't it?"

Julie doesn't know how to respond. Perhaps she doesn't have to, considering her prosthetic has started whirring audibly in response to her growing anxiousness. Coulson presses on. "Your file makes no mention about an incident of this nature, so I gather it's a recent event. Perhaps related to your nightly activities?"

Her lips press tightly together. Coulson waits a beat. "Have you told your parents?"

"I don't think they'd care if I did." -Gwen says, honestly. "It's not like they ever listen, so why would this be any different?" -she asks rhetorically, pointing at her glowing abdomen.

Coulson's eyebrows furrow in worry. "You don't think finding out their daughter is some kind of superhuman would gather their attention, just a little bit?"

Gwen sighs. "Maybe in a purely scientific sense?" -she muses. "Look, if it isn't about my grades or Kevin, my parents don't wanna hear it. They never wanted a child, and they've made it pretty clear that even if they did, I wouldn't be 'it'. But since I'm here, I might as well make myself useful and make them look better."

Agent Coulson's lips press tightly together at her remarks. "Something the matter, Agent Coulson?" -she raises an eyebrow.

"There's always something, Miss Tennyson." -he smirks tiredly. "Right now, I'm trying to reconcile the Max Tennyson I knew and admired and what seems to be his devil spawn." -he jokes.

To his surprise, Gwen actually chuckles. "We get that a lot." -she retorts. "It sucks, but we always had Grandpa Max in our corner." -she says. "To defend us when he could, and take us away when he couldn't. I really don't know why his kids are the way they are. Honestly, I don't know much about Grandpa Max at all, which became entirely too apparent after he quote-unquote 'died'."

Coulson leans forward. "What did you discover about Max?"

"Max Tennyson is a liar." -Kevin says, hurt evident on his face. "He let me believe he'd died just so he could go and probably actually die in some stupid war in space. He completely hid his past as a secret superhero from us. And - this one might interest you, Agent Coulson - he told me my parents had died in a break-in gone wrong, when they were actually murdered by people who wanted to kidnap me for my powers when I was a toddler." -he rants.

Coulson's eyes widen. "Your powers? Are you saying you're Enhanced?"

Kevin scoffs. "Of course you'd focus on that part." -he says, bitterly.

"I apologize, Mr. Levin. Please understand, S.H.I.E.L.D. strives to maintain a very strict surveillance on people with superhuman abilities. It's extremely rare that we'd miss someone like you, especially considering your...extenuating circumstances." -Coulson explains.

"I'm sure you'd like to think so." -Kevin drawls. "But doesn't the fact that you missed half a dozen teenagers with superpowers just in Arcadia make you wonder?"

Coulson tilts his head. "I suppose it does." -he admits. "Recent events have made it abundantly clear that S.H.I.E.L.D.'s handle on the superhuman diaspora isn't as good as we wish it was."

"Some would argue that's a good thing." -Kevin crosses his arms. "Superheroes shouldn't be marching to the tune of shady government organizations."

"To whose tune should they be marching to, then?" -Coulson humors him. "S.H.I.E.L.D. is by no means perfect, but our information network means we have an abundance of data for powered people to act on. The way solo heroes - solo vigilantes, really - operate is noble, but isn't it short-sighted? For all that the Devil of Hell's Kitchen has accomplished in his years patrolling the streets - for all that he's bled for his crusade - crime hasn't stopped at all."

Kevin shrugs. "Doesn't matter how much data you have if you use it to make poor choices." -he says. "You can't even protect your own agents properly - why should anyone trust you to protect the rest of us?"

The glowering teen's hit something of a sore spot for Coulson, even though he doesn't realize it; Kevin's not wrong in calling S.H.I.E.L.D. out on this, of course. The agency has a very unfortunate tendency to bite off more than they can chew - and even if it's in the spirit of better equipping and protecting their forces and humanity moving forward, the higher ups are disturbingly okay with breaking a few eggs for the proverbial omelette.

Coulson can attest to that, scar on his chest and all.

"This isn't just your worldview, is it? It sounds like this is a personal issue for you." -Coulson notes.

"You oughta know. You've read my file, haven't you?"

"Considering it makes no mention of your abilities, I may need some clarification."

Kevin huffs. "Like I said, after Max bounced, we followed the clues he left behind. Gwen found out her powers came from her grandmother. Ben got the fancy watch. And I finally got to know who I was, and why Max had to step in and adopt me."

Coulson's gaze softens. "At the risk of angering you further, I have to say I never knew Max to do anything he didn't want to do. He certainly had enough connections to place you in a good, loving family, if he couldn't or didn't want to raise you himself."

The teen would probably like to argue, but Coulson's words ring true. "I don't doubt that he loved me." -he admits. "Max was at least honest about that. But why wouldn't he tell me that my parents died protecting me? Why hide the fact that the people who wanted to exploit my powers are most likely still out there?"

Coulson narrows his eyes. "Can you elaborate? Maybe we can help you figure it out."

Kevin sighs. "My mom was a S.H.I.E.L.D. agent. My dad...I'm not sure what he was. Not human. Possibly Osmosian, considering the way my powers work." -he explains. "He was a refugee from the Nova Empire that Max helped settle on Earth. A former teammate, I think, from his Plumber days."

The agent has never heard half of the terms thrown at him, but he gets the gist of it. "So...you're half alien?"

Kevin shakes his head. "Very few sapient species can produce viable hybrids. Humans are one of them, but whatever my dad was, Osmosian or otherwise, he couldn't do it." -he says. "I'm a genetically modified human. They took my mom's DNA and rewrote parts of it so I'd exhibit similar powers to my dad's, and then shuffled a few things so I wouldn't just be a clone of her."

He places his palm, almost absent-minded, on the steel table between them. All of a sudden, like the metal's spontaneously decided to come to life and consume him, it starts climbing up his arms, up to his shoulders, his head, and down his torso. Coulson can't help but stare in wonder - this is, after all, his favorite part of the job: getting front row seats to the next stage in humanity's evolution.

"Regular Osmosians can't absorb matter." -Kevin says, just a little bit proud. It's a strange thing to see, how every part of his body is now made of steel, down to his fingernails and eyelashes. "They can only absorb and redirect energy. I can do both...and I guess my parents died because of it."

"These kids are something." -Maria Hill says, shaking her head, reviewing the footage of Coulson's interviews. The teens are being kept in holding while they decide on a course of action - hardly ideal, but they need to figure out what's going on in Arcadia and they've been rather uncooperative. Hill is surprised the younger foursome has stayed; the older teenagers vanished the moment no one was looking, and from what little they can glean, she's reasonably certain their meager fortifications couldn't hold them. "I still can't believe we missed them all."

"I have to imagine Max tried his best to keep them a secret." -Coulson reasons. "And, knowing him, his best was probably better than ours."

Hill hums. "Damn shame, that we could never get him to join up. The man was a juggernaut when he wanted to be." -she laments. "I guess he still is, just in space now."

Coulson shoots her a weary look. "I really hope we don't have to deal with another space war. Don't know that S.H.I.E.L.D. could bring me back from the brink twice."

The agency's no. 2 purses her lips. "Do try not to die again, Coulson. I don't think our finances can take another Lazarus reenactment."

"Really? Was I that expensive?"

"More expensive than the Helicarrier's repair bill." -Hill confirms, vaguely. "So, y'know. Don't go picking fights with any other Norse gods - or gods of any description, really. Not even for Captain America."

Coulson smirks. "I make no such promises."

Hill rolls her eyes at his inner fanboy showing up. "So, what are we gonna do about them?"

"Protocol dictates we Index and either release or contain any Enhanced individuals." -Coulson says, almost reflexively.

"Uh-huh. So, what are we gonna do about them?" -Hill repeats, giving him a meaningful look as she nods at the monitors.

Coulson knows what she means, of course. Protocol was then - before Iron Man, before the Avengers, when S.H.I.E.L.D.'s attitude towards superhuman beings was rather monochrome. But a lot has changed in the past two years - superheroes aren't just shadowy figures subject to urban myths anymore; they're public figures, even celebrities, known and beloved throughout the world. Some at the agency saw this coming, of course, Fury, Hill, and himself among them. Hell, even former Director Carter knew there would come a time when another paragon like Steve Rogers would rise for the world to rally around.

Probably didn't see Steve himself coming back to fulfill that particular prophecy, but still.

The truth is, however, that none of them ever imagined how enormous this phenomenon would get. In a single month, the world has gone from staring up in awe at a billionaire in power armor, to idolizing a troupe of superpowered beings - and Coulson can't imagine things calming down at all, considering how many more Enhanced are popping out of the woodwork.

Case in point, their current guests.

"I don't know." -Coulson admits. "They're good kids. Brave, selfless - everything you want in a hero. But they're still kids."

"Spider-Man is fifteen, same as Ben and Julie." -Hill notes. "He's practically an Avenger, now."

"And I'd give them a piece of my mind, if I were allowed to see them." -he grouses. "The moment we sanction teenaged vigilantes, we're playing right into what our critics assume about us."

Hill raises an eyebrow. "I know you don't like to acknowledge it, Phil, but many things people assume about us are true. We do have black sites. We do disregard most sovereign borders. And we do search and destroy any potential threats to global stability - often to the benefit of the West. To the benefit of America, even if S.H.I.E.L.D. has been ostensibly international for decades, now."

"That doesn't mean we shouldn't draw a line sometimes." -Coulson counters. "The unsavory things we do have to ultimately protect people. If we just do these things because we can, we're no better than Schmidt's little Nazi science project." -he argues.

A knock on the doorframe to their room snaps them out of their musing. "Hill, Coulson." -Agent Sitwell interrupts. "At the risk of sounding like a cliché, you should really see this."

Coulson and Hill look at each other, and follow their fellow agent. He leads them to a broader monitoring station at the heart of the facility, a plethora of screens showing the results of their survey of Arcadia Oaks. One particular display is flashing with red signs of alarm. "What's the situation?" -Hill demands.

"Some kind of anomaly in space over us, at the very edge of the atmosphere." -Sitwell says. "Extreme thermal readings, bursts of irradiated particles, the works."

"Any visuals?"

Sitwell shakes his head. "No satellites that high. We might be able to requisition one of Stark's, but it'd still take a while to maneuver into position."

Hill nods. "Do it. He owes us for the suit he stole from us, anyway."

Coulson raises an eyebrow. "What suit?"

Hill sighs. "Obadiah's."

The agent blinks. "I thought it was destroyed when Loki blew up the PEGASUS facility."

"Apparently, it survived." -Hill shakes her head. "Got taken and retrofitted by this group the Avengers are tracking. Then Supergirl defeated the guy wearing it at OsCorp, and Stark decided to keep it for himself."

Coulson winces. "In fairness, we kept it from him first. Megalomaniac pilot or not, it was Stark Industries property."

Hill shrugs. "He could've fabricated one if he wanted to." -she reasons, then turns to the monitors. "Now, what the hell is the universe going to throw at us now?"

Hala curses the name of every god she remembers, and then curses the ones she doesn't.

It was all so very fast; they knew he was coming, of course, but they never imagined that this centuries old warship could've achieved the feats it accomplished, especially faced by a sizable fleet of modern Kree vessels.

Now, all that stands between the Chimeran Hammer and Earth is her treasured Azure Lance.

"Director Brand reports they have successfully received the last of our sister ships' lifeboats." -her communications officer says.

Hala sighs to herself, in relief. The monster aboard the enemy dreadnought had at least shown the common decency not to directly target their escape pods, but the fleet's debris field had nevertheless destroyed two of them, so far.

Abigail had been none too pleased about sitting this battle out, but Hala didn't leave her much choice; her human friend has always been quite proud of S.W.O.R.D.'s battlestation and base of operations, but the truth of the matter is that Excalibur, for all of its power, is not remotely ready for the brutal reality of space combat. It has no attending fleet, no siege defenses, and its starfighter complement is small and untested - if not for its cloaking, the Chimeran Hammer would've probably vaporized it by now, had S.W.O.R.D. chosen to join in the fray.

"Fifteen-hundred kilometers and closing." -the navigation ensign warns. "The enemy ship will be in range in fifty seconds."

The Accuser grits her teeth. She's been forced far too close to Earth's gravity well, and the warlord knows it; a few well placed shots could disable her ship's maneuvering thrusters, and the planet's pull would do the rest. "We'll meet him halfway." -she snarls. "Thrusters at full! Shift shield priority to the prow projectors."

The crew grimly braces, the kick of their fusion reactor briefly managing to overcome the ship's artificial gravity. They hurtle forward, like their namesake thrown, directly in the path of their gargantuan foe.

"Dreadnought in range!"

"Fire at will!" -Hala orders.

Twin lances of white-hot plasma burst from either side of the bridge, streaking toward the Chimeran Hammer. The warship has no shields - it's an old design philosophy, long since phased out, of packing the hull with dense ablative material and using the spare reactor energy on further weaponry - so they land a clean hit, but the armor plating is so durable that the damage is mostly cosmetic.

"Minimal effect on target." -the weapons officer laments.

The Hammer immediately returns fire - a single, twenty-kilo tungsten slug magnetically accelerated to sub-relativistic speeds. It slams against their shields in an instant, far too quick for any form of evasive maneuvering - not that they could afford to let it slam against the world below. The Kree Battlecruiser reels backward, its thrusters working overtime to compensate, its protective shielding rendered offline by the direct hit.

There's nothing for it. This is a battle that will have to be won on the ground. She hopes against hope that Ben and his friends will prove victorious.

But she'll be damned if she doesn't go down swinging.

"All hands, abandon ship!" -she orders, grimly determined. "Regroup on Excalibur."

Her officers protest, but she brandishes her badge of office. The stone spear thumps against the metal floor, silencing them. "As long as I draw breath, I remain the Accuser." -she reminds them. "Protect our human allies! Make certain they can defend their home."

Hala removes her ceremonial headdress, tossing it aside. "We have a duty and a debt to the people of Earth. We have already failed as their protectors once. Don't let this barbarian embarrass the Kree Empire any further! For the good of all Kree!"

Before long, it's just her, alone on the bridge. There are only a few hundred kilometers between her and the Hammer, and the distance is closing fast. The Kree haven't had a god since the Supreme Intelligence came to be, but she's come to know the divinities of other species and cultures through her position, and she's particularly familiar with humankind's.

She prays that they let her Lance strike true.

Ben knows they're screwed the moment the Cold War-era sirens start blaring.

S.H.I.E.L.D. saw fit to put them all in the same room, which suits their purposes just fine; Ben isn't quite sure why an agency specifically tasked with reigning in people with superpowers would let them team-up, but he's not about to look a gift horse in the mouth - or, in this case, an easy escape opportunity in the improbably neglectful security measures.

Gwen's eyes glow violet for a second, and the air in the room becomes impossibly still. "We can speak freely now." -she says.

"Silence spell? Nice." -Kevin smirks.

The redhead shrugs a mild blush off. "I've had a lot of chances to practice it. Makes my escapades a lot easier."

Julie purses her lips. "We really need to do something about that."

Gwen waves her off. Not really the time for that particularly well-worn conversation topic. "So, what's the plan?"

"I could just go Four Arms and bust us out of here." -Ben suggests. "Make up for my lousy showing earlier."

Kevin shakes his head. "Too messy. Plus, it'd definitely make them hostile moving forward. We can probably take this encampment without much of a problem, but the larger S.H.I.E.L.D.? Hell, they might even sic the Avengers on us."

"Okay, slightly less confident about those odds." -Ben admits. He might have the right aliens for it, but one at a time is a hard limit when imagining, say, Supergirl and the Hulk coming at him at the same time. "Something sneakier, then?"

"We could just wait for Claire to spirit us away." -Gwen says. "It's almost been two hours."

Claire and Toby bounced, of course, but they didn't do it for selfish reasons; given S.H.I.E.L.D.'s presence, and the fact that they witnessed their exit from Trollmarket, they needed to make sure the hidden city's defenses were properly notified and fortified. She said she'd be back for them a couple hours afterwards before she left, too.

"That's the safe choice, but it's also putting a lot of pressure on our new friends." -Ben says. "S.H.I.E.L.D. can probably track the dark energy from Claire's bone stick thingy, too, if they could detect that the Omnitrix is an alien design."

Kevin hums. "Agreed. Plus, we really should be able to escape on our own."

Ben nods, sagely. "That's, like, a vital superhero skill."

"I know you guys don't have to worry about, like, parental units or anything, but we do." -Julie fretfully reminds them. "I should've been home by now. Mom and dad must be worried sick."

"I left a clone at home, so I should be good, but Julie's right. We need to get out of here, and pronto." -Gwen says.

And then, the sirens go off.

They all snap to their feet; the sirens are tested every year, so they know the sound well, but the tests are performed in January, not the middle of summer. The door to their holding room opens, revealing a grim-faced Coulson. "Follow me." -he says.

The teens look at each other, and follow the agent. The makeshift base has sprung into barely contained chaos, S.H.I.E.L.D. personnel swiftly taking down their prefabricated installation, preserving their findings and gearing up for combat. "What's going on?" -Ben wonders as they step outside.

Coulson points at the sky.

The cause of the commotion is immediately apparent; the twilight sky is playing host to an artificial meteor shower - debris from what appears to be several explosions in space, burning down as it hurtles down toward Arcadia and its surrounding area. Some of the larger chunks even seem to be making it to the ground, but thankfully, none are headed to the city proper.

"That's the Kree blockade." -Kevin realizes. "Hala's forces, they're...gone."

Julie pales, covering her mouth in horror. "She can't be…" -she mutters.

Ben can't quite believe it, either. The Accuser and her fleet seemed all but untouchable to him, a bastion of Kree military might - even if they were really traitors to their Empire. Now, all that's left of them is burning up on re-entry.

"You know what's happening? Do you know who's responsible for this?" -Coulson urgently asks, uncharacteristically shaken.

Ben does. It really can't be anyone else - not now, not here, not when he secretly wields one of the most powerful artifacts in the universe in the otherwise idyllic little town that is Arcadia Oaks. He nods. He's surprisingly calm, for someone whose time has likely come.

"Vilgax has returned."

Maybe some of you familiar with my StarCraft x Halo x Mass Effect crossover, Whispers of Darkness. Very popular, but also quite bloated and directionless - really, a staple of my earlier works. At any rate, there are a lot of space battles in that fic, and it felt pretty good to flex my sci-fi muscles, even if the battle between Vilgax and Hala's forces was pretty simple by sci-fi standards.

No new aliens this time around, so no new codex entries, but I can tell you that the name of this chapter is inspired by Norse mythology. Fimbulwinter is the immediate prelude to the Norse apocalypse, Ragnarok! It's just a metaphor, though, we're not in Thor: Ragnarok territory yet, not by a longshot. We'll see if Ben and co. can prevent this particular armageddon!

As always, thank you for your attention! Make sure to comment or message me if you have any questions about this story. Look me up on Twitter as Darthkvzn or Tumblr as darthkvznblogs if you'd like - and on Ko-fi, as Darthkvzn, if you like what I do and have a buck to spare.

Until next time!