Harmonic Vengeance

Chapters

Equestria: Waking Up
Earth: Waking Up
Equestria: Chaos Spreading
Earth: Planning
Equestria: Cleanup
Earth: Thoughts and Conversations
Equestria: We Have a Problem
Earth: The Deep Breath Before the Plunge
Equestria: If at First You Don't Succeed...
Earth: Coming Together
Equestria: ...Try, Try Again
Earth: Going Home
Equestria: Arrivals
After-Credits Scene 1
After-Credits Scene 2
Prologue: So Discord and Loki Walk Into a Bar...

Equestria: Waking Up

Tony Stark yawned, stretched, and rubbed his eyes, noting sleepily that his hands felt really funny, kind of like big blocks. His eyes drifted open. What were those weird blue things in front of him? He tried to reach out a hand to touch one, but the blue thing moved too.

His brain began to wake up, and he began to realize what was happening. Those were his hands, only they weren't hands. They were... hooves?

I am a horse.

I am a talking blue horse, and I have the memories of a talking blue horse.

And I have wings.

His mind stumbled, trying to process this information. Amidst a confused jumble of That's not possible and But what about Pepper? and Wings are pretty cool though, look on the positive, Tony, one thought floated to the top.

This is gonna be a bad day.

Steve Rogers noticed several things at once.

The first was that his room smelled like hay. The second was that, in some way that he wasn't awake enough to be sure of the specifics yet, his body was different. The third was that he had a whole flood of memories that weren't his.

In fact, he had a whole other identity. It took him a moment to gather the threads of it and figure out who this person was, the person he was that wasn't Steve. It took him several more moments after that to deal with this knowledge, because it was just so... weird.

He was a Southern pony who farmed apples, he'd defeated pretty much the personification of darkness with the magical representation of Honesty, and he was a girl.

Director Fury had earned another $20.

Natasha's instincts blared at her that something was very, very wrong. She leaped out of bed, scanning her surroundings, trying to take everything in at once. Fancy room, second floor. No immediate threats--nothing's even moving. Why am I standing on four legs? Weird memories... I'm "Rarity"...

She shelved This is literally impossible away for now. Time enough for that later. Five friends. Very close. Would likely detect any action not similar to Rarity. Can I act well enough to convince them? Probably. But if I told them, would they help me? Also likely. "Never trust anyone" was ingrained into the fiber of her being, but trust and dependence on friends was ingrained into Rarity's. They struggled for a moment, but Natasha inevitably won out. Twilight recently mentioned a race that can turn into anypony. With her tendency to panic, she'll assume I'm one of them, probably attack me before I can even finish my sentence. A good kick to the horn can disable a unicorn for a few seconds... and reinforce everypony's suspicions.

If I had to fight them all, how would I do? None of them are trained for combat... actually, Rainbow Dash might be. Anything the Wonderbolts are required to do, she's been practicing since she was eight. Applejack is incredibly strong, and Twilight's magic will cause serious trouble once the horn kick wears off.

If I were me, I could probably still take them, but I'm a horse. But I didn't have to learn how to walk on all fours, and- She tested her horn on a book near Rarity's bedside, and watched it float upwards, surrounded by a blue glow- and I didn't have to learn magic either, Rarity's instincts are still here. But Rarity doesn't have the instincts required in a fight. I have fighting instincts, but they're human instincts. I may be able to react quickly, but there's no guarantee of being able to react correctly.

She took a deep breath. Summary: Don't get caught.

Bruce Banner's last memory was falling out of the sky. By all logic, he should be sitting in a pile of rubble and aching all over, or maybe even dead. But instead, he was lying in a warm, comfortable bed.

But wait, this couldn't be his bed. His bed in India was barely a cot, and on the helicarrier it was little better. He opened his eyes, looking around, trying to place where he was. He failed utterly.

It was a whimsical-looking place, like something out of a cartoon. The curved and slightly bumpy walls suggested something naturally made, not built. There were no planks, just smooth wood. Books lined almost every wall. He'd never seen the place before, yet he felt like it was strangely familiar, like it was home. This is my home, these are my books, this is my library.

He picked one up to examine it, but only when it was laying on his lap did his half-asleep mind realize what he'd just done.

That book had been sitting on a shelf.

Halfway across the room.

And he'd picked it up.

He sat up, trying to clear his head and force himself awake. As he got less sleepy, he noticed that he was sitting in an odd position, something like a dog or a cat would. He looked down at his body.

Purple horse! PURPLE HORSE!

Yet, just like the library, something was familiar about this purple horse body. Something in his brain tried to insist that it was a pony, not a horse. He ignored it. That was an extremely pedantic distinction and he had more important things to worry about--like the fact that he was a PURPLE HORSE.

Thor had never had so much energy in his life. He bounced out of bed and glanced around the pink room, talking to himself as his cognition pieced together that he was a pony named Pinkie Pie. He knew he should be trying to find Loki and the tesseract, but it was hard to be mad when he was in a completely new world to explore, with completely new magic, and he felt so. Alive.

He decided to check and see if he could summon Mjolnir, but after nearly a minute of holding out his hoof and willing the hammer to come, he had to admit defeat. Still, this wasn't nearly as bad as last time he ended in a totally unfamiliar world. This time, he already had some friends here, kind of, and he wasn't completely clueless about how this realm worked.

He'd have to find a way to get back eventually--as soon as he could--but for right now, he could make this work.

Clint Barton felt a little woozy. Loki! What did he do? The last few weeks, I've been... everything I was got rewritten, I thought I had to stand with him... I tried to kill Natasha!

He put a hand to his head, not noticing how much like a hoof it felt. Where was Natasha? Had he hurt her? His memories felt all fuzzy...

Except for a few that were really clear...

...A few about a world called Equestria, filled with magical ponies.

What did Loki DO?

Sighing, he got to his feet and examined his surroundings. "Can't I get just a few minutes to rest?" he complained quietly. This room was from the weird pony-memories, not from his own.

Either Loki gave me weird memories and hallucinations... or those memories were real.

He swished his tail, flapped his wings, then forcefully kicked the wall. It hurt. This wasn't some kind of dream or hallucination.

"Dangit."

Earth: Waking Up

Twilight Sparkle hurt all over.

She was sitting in a pile of rubble. As she groaned, waking up, a voice nearby said, "You fell out of the sky."

She opened her eyes and glanced down at her body. It was strange and unfamiliar, and it was male. It was naked, which wouldn't normally have given her pause, but a strange feeling told her it was different now. Nakedness was a taboo in this culture.

"I saw you fall," the voice continued, "big and green and totally nude."

The words came out of her mouth without conscious thought. "Did I hurt anybody?"

She briefly wondered why she hadn't said "anypony", but that same instinctive sense told her that that wasn't right either. She wasn't in Equestria anymore--she wasn't even Twilight Sparkle anymore. Her name was Bruce Banner... or, according to some, the Hulk.

Which was why she hurt all over right now; she'd fallen from the sky after a fight on the helicarrier.

"Nah," the man was answering, "nobody in here but me. Sure scared some pigeons, though."

She nodded with relief. He pulled out a bundle of clothes and tossed them to her. "Didn't think they'd fit you, 'till you turned into a regular-size feller," he added, as she gratefully put them on.

Remembering her manners, she said, "Thank you. Thank you very much." A stranger had crashed through the roof of this building--probably his job--and his first thought had been to give them clothes. That might have been common in Equestria, but here on... on earth, that was growing increasingly uncommon.

"Eh, don't mention it." He watched her dress for a while, which felt a little uncomfortable, but it would've been just as awkward if he'd looked somewhere else. Her mind was busy processing the Loki situation, and she thought she had a solution. Now she just had to-

"Are you an alien?" the man asked conversationally.

Caught off guard, she only said, "Huh?"

"From outer space, an alien."

"No," she said. Maybe, she thought.

"Then, son, you've got a condition."

If by a condition, you mean a blast of gamma radiation that turns me into a destructive monster if I get either angry or hurt, destroying everything around me I care about, then yes. Aloud, she didn't even answer that remark. Instead she said, "I hate to burden you further, having already destroyed your... workplace?" He nodded. "But I need to get to New York, as quickly as possible. Can you help me?"

Pinkie Pie was-

"Thor all over! Heehee, get it? I'm Thor all over?"

Pinkie! Stop your fourth-wall breaking and your terrible puns and let me narrate!

"Hmph. Party pooper."

As soon as Pinkie's eyes flickered open, she knew what was going on. She didn't have to wait and process. Quickly, she stood up and summoned Mjolnir from a few dozen yards away. "All right! Let's go stop Loki and save the world! Best! Adventure! EVER!"

She lifted the hammer and twirled it around and around like the blades of a helicopter, quickly taking off into the bright blue sky.

Fluttershy was terrified. True, she was usually terrified, but it was much more deserved this time. She was in a totally weird place with memories of Clint Barton, a secret agent. And that meant memory after memory of hurting people, even killing them.

Oh, and there was that small tiny totally insignificant detail where he'd been brainwashed by Loki and killed a bunch of other people and helped him make a portal to invade the world!

She forced herself to take deep breaths. Clint's brainwashing had gained one valuable piece of information; the day when Loki would attack. Today.

She had to warn the others. Clint is confident. He knows what he's doing. I can be confident too. After all, I'm him... kind of.

Internally, she was both whimpering and screaming with panic, but she kept them both down inside. She thought of Clint's secret family, his wife and children. Then she imagined Loki and his invasion of aliens attacking, destroying the farm. NO. I won't let that happen. The anger boiling up at the very thought of something happening to that innocent family was enough to get her up and moving. She couldn't waste time panicking, not if she wanted to prevent that from ever happening.

Applejack's eyes opened. She was somewhere completely unfamiliar, and a quick glance at herself showed that her body was unfamiliar as well--yet part of her also recognized both. The name "Steve Rogers" popped into her head, as well as a long history of fighting for America, living and breathing patriotism, and a very current danger from Loki and a tesseract.

Some ponies called Applejack 'simple', and maybe they meant that she wasn't very smart. But the way she saw it, 'simple' meant that her world was clear, straightforward, black and white. She didn't have to hesitate even for a second; she knew what she was going to do. She was going to save the world.

Then she could worry about finding her way home.

Rarity absolutely adored her hair. Springy, bouncy little red curls. They were adorable--and so practical! While she personally wouldn't have worn a short mane for anything, this hairdo was both stylish and out of the way.

The constant black clothing was a little drab, though. Now, a green dress would really make that hair pop, not to mention bring out her eyes! Yes, perhaps with some bronze accents...

"Focus, Rarity," she murmured. "Save the world first, design fashion second."

Rainbow Dash was... an egghead. Okay, she was an amazing, bold, confident egghead, who used his egghead-i-ness to become a totally awesome superhero. But still... an egghead. Come on!

Still, she was Iron Man, and she was totally awesome, and also it was partially her job to save the world. And she wasn't in Equestria. This wasn't likely to be a quick standoff, leaving everyone unharmed. Here on earth, people got hurt. Innocent civilians were caught in the crossfire. People got killed.

Well.

Not on her watch.

Author's Note

So, you guys should know: I'm a really terrible author. I'm not going to make a schedule to update, because I'll never stick to it anyway. Thing is, though, most of the chapters are already written. All I'll need to do is publish them, and I'll still forget. So if it's been a while and I haven't updated, shoot me a comment or a PM and yell at me, okay? Thanks.

Equestria: Chaos Spreading

Author's Note

And straight into the action! I won't always cover everyone's POVs from here on out; some of them see more action than others, and in different chapters.

Equestria: Chaos Spreading

The first thing Tony wanted to do was experience flight. Of course he'd flown in the suit before, but it just wasn't the same. And even he knew that memories were one thing and the real experience of flight was another entirely.

He stepped out the door and spread his wings. Don't focus too much on how you're doing it; it's just instinctual. Just like how if you focus too much on walking, you can't. Just do it. Don't think.

Telling the obsessive genius not to think about something. Great plan.

He forced thoughts out of his mind, and before he could second-guess himself, flapped his wings, taking off. He angled upwards, gaining altitude quickly. With hardly a flick of a feather, he turned right, then left, laughing out loud. This was amazing!

He swooped downwards, and pulled up just in time to avoid hitting his house, but close enough to skim the roof. He rolled, combining it with another short dive. Then he regained the altitude he'd lost. He rolled again, pausing in the middle of it to glide with his wings spread upside-down for a few seconds before righting himself. It was so exhilarating, he almost didn't notice the pink cloud he whooshed past.

Almost.

He whirled around to look at it as it floated past. He couldn't remember working with a single pink cloud in the weather factory or as Ponyville's weather manager; even in Equestria, this wasn't common.

But wait, sometimes weather over a lot of sand or reddish dirt will pick some of it up, and you'll end up getting pink clouds. That happens, even on earth, it's jut rare. That's all this is, just dusty clouds.

But shouldn't it be staying put, instead of moving on its own?

All Rainbow's experience was telling him that clouds should stay exactly where they were placed, but Tony himself had never actually see them to that, and weather shouldn't work that way. It didn't make any sense. So maybe Rainbow Dash was wrong. All her experience in weather management and cloud control was mistaken. That was it.

He followed the cloud anyway.

Steve Rogers had gotten straight to work. Even if he wasn't really Applejack and he needed to find a way to get home as soon as possible, there was a lot to be done around the farm. Right now, he was picking a crop of corn. It wasn't a large part of their profits, but it helped supplement. As he worked, rain clouds began to roll in, but he didn't even look up. He and Applejack were both used to working in the rain.

Neither of them were used to working in chocolate milk.

Corn popping abruptly was also not a common occurrence in Equestria, as far as either he or Applejack knew. Maybe it was a prank of Rainbow's. Could she have gotten Spike to help? Did he breathe actual fire, or only send letters?

Wait, there was Rainbow now! Maybe it was a prank and she was watching the reaction. "Rainbow!" he hollered, as loudly as he could. "What's goin' on?"

"I think it's dust in the air!" she called back. "It's turning the clouds pink and the rain brown!"

"Well, that would make sense, if the rain weren't chocolate milk!"

"It's what?" She ducked under a cloud and drank some. "Woah. That is weird. Lemme guess, the clouds are cotton candy?"

"How should I know? You're the one up there!"

Rainbow Dash sighed, scooped up a ball of cloud, and licked it. "What, seriously? THAT WAS A JOKE! A JOKE!"

You already knew you could act like Rarity, Natasha, she told herself. That shouldn't change just because everything is nonsense now.

"Hello, Applejack!" Natasha trilled. "I heard about your troubles and I'm here to help in any way I can! ...As long as it doesn't involve me getting wet. Or dirty. Or out from under my umbrella."

Applejack gave her an annoyed look, but not a suspicious one. See? That was exactly what Rarity would say. She breathed a mental sigh of relief.

Pinkie Pie ran past, shouting, "What wonder is this? Chocolate milk rains from the heavens!"

"Huh?" Rainbow Dash said, but Pinkie was already gone.

Clint had a feeling something weird was going on. Call it a hunch, call it a vibe, call it chocolate milk raining from pink clouds; whatever you called it, things were strange. And Sweet Apple Acres, fields covered in popcorn and giant apples weighing heavily on the trees, was the epicenter of the oddity.

Some of Fluttershy's animals were eating the giant apples off the trees. Clint approached them. Gentle and polite. That almost always does the trick.

Pinkie Pie whizzed past him, marveling loudly at the chocolate milk. She appeared to be making laps of the orchard. He ignored her and moved towards the animals.

He leaned towards a bunny and a squirrel. "Excuse me," he said softly, but firmly, "Applejack and I would both appreciate it if you left those apples alone. She really needs those, to get enough money to get by. Can you do that? For me?"

To his delight, they nodded and hopped off the tree. "Come on," he instructed. "Let's go stop the other animals, then find you all something better to eat."

But by then it was too late. Not only they, but every other animal who'd been eating the apples, grew long, deer-like legs and began running around. "Wh- what? What?" For once, he was completely at a loss.

Bruce Banner had to do something. He was the leader of this group now, and something was happening. The others would need him.

But I'm not a leader! he objected. I have no clue what I'm even doing!

But you have her memories, he argued. You've got all the experience. And you don't have to have the solution by yourself, just a way to combine the talents of your friends to work around the problems facing you.

Ugh, fiiiine.

Not quite what I was looking for, but I'll take it.

He got to his hooves, took a deep breath, and trotted out the door, towards the center of the chaos.

Earth: Planning

Rainbow Dash glanced through the portfolio Tony had been given at the start of the mission. A figure jumped out at her, and she examined it for a moment, then ran some numbers through a calculator.

She stared at the figure, then grabbed a pencil and pad of paper and started running through the helicarrier, still punching in numbers. She had to talk to Banner about this, right away!

"He's going to do it today," Hawkeye announced softly.

"Any idea where?" Captain America asked urgently.

"N-no, he didn't tell me that--I'm sorry!"

"It's all right, no need to fret," Steve reassured.

Hawkeye mumbled something incomprehensible as Tony ran in, holding a calculator in his teeth and scribbling down numbers in a notebook. He dropped the calculator into his hand and asked, "Where's Banner? I need to talk to him!"

"Bruce FELL OUT OF THE PLANE!"

Tony turned pale. "He what? No, he- he can't've-"

"Well, he did!" Steve snapped.

Natasha spoke up. "What did you need Banner for?"

"I was looking at the energy required to activate the tesseract, and- where's Thor?"

"Thor fell out of the plane too," Steve sighed.

"What, seriously?" Tony looked seriously upset now. "Anyone else? Maybe Coulson fell out of the plane? Director Fury? Barton?"

"I'm right here, Tony."

Steve put his head in his hands. "Nobody else fell off, but Coulson got stabbed."

Tony threw up his hands and screamed. Then he took a few deep breaths. "Okay. Do we know for sure Thor and Banner are dead? If anyone's going to survive a 30,000-foot fall, it's the Hulk, and if anyone else is, it's an Asgardian like Thor, especially one that can fly, also like Thor."

"If anyone can do it, it would be one of them," Natasha said. "That doesn't mean someone, even them, definitely can."

"Thor was dropped inside a glass cage. There was no way for him to fly," Steve added.

"NOBODY IS DYING ON MY WATCH!" Tony shouted, slamming his hands on the table. Everyone flinched, especially Clint.

Natasha wisely changed the subject. "What were you saying about the tesseract? That could be valuable information for planning out next move. Agent Barton says Loki will strike today, so we need to discover where he'll be, and soon. We can try to locate the rest of the team later."

Tony sighed. "All right. Well, in order to activate the tesseract to create, Loki would require a huge amount of energy. He'd need something that produces more than twice the amount a whole city takes! Maybe if he sucked all the power from a really, really big one, like New York or Hong Kong or, I don't know, Tokyo, it could be enough, barely. But stealing all the power from a whole city would be nearly impossible! He just doesn't have the energy, and there's no way he can get to it as quickly as he has. He can't possibly be attacking today!"

"So," Natasha interjected, "he'd need something like... a giant arc reactor?"

"Exactly!" Tony gestured towards her. "And where on earth is he going to get something like- Oh. Oh shoot. Everyone suit up, we leave in five." He turned and ran out of the room again, this time shouting, "Director Fury!"

"What are you doing?" Steve called after him.

"Evacuating New York! I'm not going to let anyone get caught in the crossfire."

Natasha tilted her head. "Guess he's really serious about that 'nobody is dying on my watch' thing."

"You bet I am!" his voice called from the hallway, his footfalls rapidly diminishing.

Equestria: Cleanup

Shoulders back. Stand tall. Project confidence. You've got this.

"Don't worry, everypony!" Bruce Banner called. "I have a plan. Rainbow Dash, can you bust those pink clouds like normal ones?"

"One second." She flashed off in a burst of speed, and just as quickly was back, looking a little stickier and pinker than before. "No. No you cannot."

"All right. Good to know. Can you herd them all together, into a big clump?"

"One second again." Zoom. A pause. Zoom. "Yes you can."

"Great. Do that." Zoom. No return zoom. "Applejack, once they're gathered, lasso them down to earth."

"Pegasi only touch clouds through magic. I don't think my lasso will--wait a second. Cotton candy. Right."

"Cotton candy?"

"That's what the clouds are." She pulled a variety of ropes out of her saddlebag and started tying them together, trying to make a lasso long enough to reach the sky.

"Figures. Fluttershy- what happened?"

"They ate the apples and now they're deer things."

Recalculating.

"Is cotton candy edible for animals?"

"Before things went insane, certainly not. Now? Who knows?"

Bruce tapped his hoof on his chin. "Applejack?"

"Yesh?" Her speech was muffled by the rope in her mouth. Her lasso was incredibly long by now.

"Do you want to sell all that popcorn, or just get rid of it?"

She spat out her rope. "Little dirty to eat now."

"For humans. Fluttershy?"

"Yes, they can clean that up."

Rainbow Dash returned, panting. The clouds had gathered into a lump, and were too sticky to separate themselves again. "I don't want those clouds to get loose again. We need to find a way to get rid of them permanently."

Bruce could've sworn a physical lightbulb appeared over his head. "Pinkie Pie!"

She stopped circling the grounds and stood at attention. "Yes, Twilight?"

"How many recipes do you have that involve cotton candy?"

She paused. Bruce had half-expected her to shout out a random figure like "537!", but instead she merely said, "I have many. Why?"

"We need to dispose of this." He waved a hoof at the massive load of cotton candy Applejack was tugging down to earth. "Can we count on you?"

She nodded. "I shall take this over to Sugarcube Corner." She took the rope from Applejack and led the cloud away. It was still floating a little above the ground.

"She seem weird to anyone else?" he asked.

"Darling, this is Pinkie Pie we're talking about," Rarity said. "She's always weird."

"True. Rarity, can you use that spell for resizing dresses on those apples?"

She pondered. "I can certainly try." Bruce accompanied her to the trees; it would be more efficient if both of them could cast it at once. Twilight (and therefore Bruce) was magically sensitive enough to pick up the spell as Rarity began to cast it, and soon they were both working, struggling to force an apple to shrink.

"This... is the most powerful... magic... I've ever... fought!" Bruce groaned, as the apple shrank slowly and reluctantly. Sweat was pouring down both of them. Rarity barely even noticed. She, too, was panting and grunting.

"Darling... I'm really... not sure this will..."

SPROING.

The apple rebounded against their spell, growing even larger than before. Both of them felt it snapping against them, like a rubber band stretched too tightly; Rarity put a hoof to her head. Bruce felt the headache from the backlash too.

She sighed and turned to Applejack. "I'm sorry."

"Don't be. Ya helped loads with everythin' else. The apples'll keep until we can find another solution."

Spike ran up, holding a letter in his claws. "Twilight! This just came in from the princess."

Bruce picked it up. The magic of telekinesis felt really cool, actually. He skimmed the letter swiftly. "The princess needs us in Canterlot. Doesn't say why. Good thing we're all right here--no, not Pinkie, we'll have to pick her up. Anybody know the train schedule?"

Rainbow raised a hoof. "Used to live by the tracks. It was really noisy, but the upside is I've memorized the schedule. Unless they changed it, there's a train for Canterlot in about five minutes. We can be there in half an hour, it's so close."

Bruce nodded. "Great. Let's go!"

Earth: Thoughts and Conversations

The city of New York came into view. Finally, Rainbow thought, that flight took FOREVER.

She had two objectives: Stall Loki so the Quinjet carrying the rest of her team (markedly slower than the suit) had time to arrive, and get the new suit. If she could, she'd also disrupt the tesseract's processes, but she doubted it would be that simple.

She swept over the skyline, pulling up at the top of Stark Towers. Sure enough, on the roof, a bright blue glow shone. She moved in towards it, noting the absence of either Loki or Selvig. Makes things easier for me. Her arms lifted and fired the repulsor rays. Who named those, anyway?

The shockwave blew her back at least five yards. "It appears to be surrounded by some kind of energy field," Jarvis remarked helpfully.

"Nothing can ever be easy, can it?"

She dove towards it. Maybe it wouldn't allow energy in, but would it allow the suit?

No. It would not.

Flung backwards again, she shook herself, then turned and started descending towards the landing strip. "Fine. Looks like it'll be a longer challenge. We need the new suit."

"Sir, it's not ready for deployment-"

"It'll have to be, we're out of time. We can lose a few of the decorative touches."

The robotic version of a sigh. "Very well. I'll do what I can."

She was Twilight Sparkle, and she knew magic.

She was Bruce Banner, and she knew science.

This mess was a bit of both.

New York city, according to the stranger whose building she'd wrecked, was about an hour and a half away. That meant lots of time to think. She had some pressing questions about the implications of this whole deal on various philosophical fields (If I have Bruce's memories but I'm not him, then identity must be more than just the sum of your memories) but those weren't urgent. What was urgent was the tesseract.

Is there a way to shut it down? According to Aristrotle, it's far easier to combat magic by using the same magical signature. This is why it's so much easier for a unicorn to undo their own spell than for another unicorn to undo it. In this world, what's the closest thing to magical signatures? Maybe the radiation output they were talking about? But what has the same reading as-

It suddenly clicked in her mind, and she nearly skidded to a halt with the impact of the realization. Of course! It was so simple!

She hit the gas harder, moving in between cars. Technically, it was illegal, but this was an emergency. She had to get to the others as fast as possible. They needed to know this.

Rainbow Dash was not a good liar. Tony Stark was an excellent liar. With his memories, she had to be at least halfway decent. The math totally checked out.

Ish.

She was not surprised to find Loki inside the building, but she was definitely annoyed. Worse, she had to get past him to reach the wristband that Tony's newest suit required for identification. She walked towards the bar, trying to mimic Tony's confidence, ease, and casualness. "Can I get you a drink?"

It had been decent, she reflected. Not quite Tony's level of flippantness, but it was passable.

"No, I don't think so, Rainbow Dash."

Halfway inside the bar, she froze. "What did you say?"

"You heard me."

She whirled, slamming her hands on the counter. "This was you, wasn't it? You put me here! And I bet you also left the actual Tony, who happens to be a jerk, in my home, so he can drive away all my friends, who just happen to be the most important thing in my whole life!"

He laughed. He laughed. Loki was actually enjoying her fury. "You still don't get it."

"Get what?"

"These 'Avengers' of yours are your friends now, and they're all you're going to get!"

Something clicked in her brain. He enjoys this. Continuing it is the best way to keep him distracted. He can do this for hours--so let's make him. Almost absently, she slipped the bracelet on her wrist. "What do you mean?" she demanded. "There has to be a way to get back!" Doesn't there?

He snorted. "Of course not. Why would I go to the trouble of bringing you here if you could just get back?"

Something inside her crumbled. "But how did you bring me here in the first place? It must be reversible!"

"I had a little help from the other side." He chuckled. "I'm afraid the connection is one-way."

"No!" she shouted, exaggerating a little. "That can't be true!"

"Can't it?"

He was lying, he had to be lying. The connection couldn't only be one way. Right?

"Prove it!" she demanded.

"As I already said, I had help from your side of the equation. The way I see it, either your precious friends defeat him, closing the link for good, or he destroys your home until there's nothing for you to even go back to."

It couldn't be true, it couldn't, it couldn't...

...but saying that wouldn't change anything, if she was wrong, and it looked like she was.

Equestria: We Have a Problem

"Princess Celestia!" Bruce called, galloping into the palace, with all Twilight's friends right behind him. "We came as soon as we could!"

The princess turned, her iridescent mane flowing. "I'm glad you're here," she said, sounding more serious than Bruce could ever remember her being. Bruce frowned, worried.

She turned again and began to walk up the palace stairs to a long hallway full of stained-glass windows. "What is it?" he asked, trotting after her. "Is it about the strange weather?"

"This goes much deeper than that, Twilight."

Rainbow Dash interrupted. "Can we have the short version, and a little less vague?"

The princess nodded, acknowledging the concern, and pointed to a stained glass window depicting a bizarre creature surrounded by two ponies and wreathed in rainbow light. "That's Discord. He's a spirit of chaos and only the Elements of Harmony can stop him. You ponies represent and can wield the Elements. I need you to take them and stop him."

Wow. That really was the short version.

But would they work with Bruce instead of Twilight? There was only one way to find out. He looked up at the princess. "We won't let you down," he pledged.

As they talked, they'd been walking down the hall, and now they reached the doors of a massive vault. Celestia placed her horn inside a hole in the center. Different parts of it lit up in an impressive display. It swung open, and Celestia pulled out a blue box embedded with many gems. Judging by Rarity's face, they were of great quality and value.

The princess opened the box, then gasped and let it fall. Everypony crowded around, trying to see.

The box was empty.

"No!" Princess Celestia shouted. "Only I can open that vault, how could they be missing? This doesn't make any sense!"

A low, sinister chuckle filled the hallway, making the fur on the back of Bruce's neck stand up. He didn't have to ask who that voice belonged to.

"Make sense?" it asked, in a mocking tone. "Oh, what fun is there in making sense?"

Celestia stomped a hoof. "Discord! Show yourself!" she demanded.

With a flash, the stained-glass image of Discord came to life and began to speak. "Oh, so uptight, Celestia." At his words, the different colored strands in her mane began to separate and braid themselves tightly together. "You really should just unwind." Now they drifted apart until she looked like a many-colored plasma ball.

"Stop it, Discord!" she shouted, stomping again. "Tell us where you've hidden them!"

He slithered over to a different stained glass window and sat there, leaning against the image of Twilight and assuming a flirtatious manner. "Only for you, Celestia."

"Last time you flirted with me, I turned you to stone, and don't you forget it!"

"Hmph. Well, if you're going to be so cold, Celly-"

"Do not," she mumbled through gritted teeth.

"-perhaps I won't tell you after all."

"Discord..."

"Fine, fine. But I'll only tell you my way. There are three parts. Here's the first one: A fortress of defense, a bastion of might, a castle where the wise teach the young to fight. An armory of weapons, sharp as hooks, are wrapped in leather and shelved as books."

Bruce found the answer instantly, but decided not to let Discord know. "And the second riddle?" he asked warily.

"I stand, tall, reaching towards the sky, but every year, come fall I die."

That one was even easier! He pretended to think it over carefully, but inside he was rejoicing. Discord paused for a few minutes, then began speaking again. "Third riddle: Grew on a tree, two times three, these are the key, to defeating me!" With a final disturbing chuckle and a flash of light, he was gone, and only his stained-glass image remained, frozen once again in his old picture.

"Well, that last one was definitely the Elements," Rainbow Dash said.

"Grew on a tree?" Applejack reminded her.

"Actually, yes," Princess Celestia said. "That was where Luna and I found them, millennia ago, to defeat Discord."

"And I know what the other two are," Bruce announced. Everypony turned to him. "The first riddle is a library, and the second is a tree. If I had to guess, I'd say each one is narrowing down the field. It's a library, but there are thousands in Equestria. Only one of them is a tree, though. So I think we need to look in my library tree for something related to the Elements, and that's where it'll be."

Princess Celestia nodded. "It's a good place to start, at least. But you should be warned: Discord is a trickster. The obvious meaning is not likely to be what he actually intends, and it's possible that he gave you a fake clue. He certainly doesn't intend to let himself be imprisoned again; he'll try to keep you from them, or else allow you to think you've won, but secretly give you fake Elements, or do something to make you unable to use them."

"Thanks for the vote of confidence," Rainbow muttered. "Come on, let's get back to the train."

"That won't be necessary. I'll send you with sky chariots. Then, even if the Elements are not within Twilight's library, you'll have swift transportation to the next place you wish to search."

They thanked her, and after a thankfully uneventful flight, they found themselves in front of the library. "All right, girls," Bruce instructed them, "look for anything related to the Elements."

They nodded and scattered. It should only take a few minutes, Bruce thought. The library is pretty small.

Sure enough, after a short time, Rarity's voice rang out triumphantly. "I've got them!"

Everypony galloped towards her, in the central room of the bottom floor. "Where were they?" Bruce asked, before noticing the open book on the floor and the hole dug out of the pages. "Ah." That's the book about the Elements. Makes sense of the sixth riddle.

Rarity floated each Element over to its respective Bearer, and soon they were all clad in the magical gems. Some deep magical sense of Twilight's told Bruce that these were the real Elements, and Discord wasn't tricking them. At least, not about that.

He was pretty sure how Discord was invalidating the Elements: him. He wasn't Twilight, and he certainly couldn't pretend hard enough to fool the Elements. It was worth a chance, he supposed. And what would happen once--if, he corrected himself--it failed? Nopony would realize what had happened. Should he come clean? How would they react?

Time enough for those worries later. He had to at least make an attempt.

They trotted out the door. Discord was waiting on a weird throne made out of swords, directing cotton candy clouds. The roads, and the entire hill he sat on, were covered in a blue and yellow checkerboard pattern. Discord turned as they approached, yawning unconcernedly. "Oh, dear, I see you've found the Elements. Clearly my doom is near at hand."

His casual dismissal infuriated Bruce. "Yeah, it is!" he shouted, noticing how lame it sounded too late. Quick, think of something snappy. Um... um... Oh, forget it. He won't be laughing when it works.

Instinctively, they formed a V formation. Bruce narrowed his eyes. "All right. Let's do this."

His crown lit up. Behind him, the other Elements began glowing. Oh my goodness, it's working. A rainbow swirled around them, lifting them into the air. It's working it's working it's working-

The rainbow flickered and died, dumping them painfully in a heap on the ground.

I could be wrong.

Author's Note

No, that was not Dislestia. He flirts with her only because he knows it makes her uncomfortable, and he loves making people uncomfortable.

Earth: The Deep Breath Before the Plunge

Rainbow Dash had allowed Loki to taunt her for ages, mocking her, telling her she'd never make it home. Every minute he pushed her farther was a minute the rest of the team had to make it to New York. But finally, she snapped. Enough was enough.

She moved out from behind the bar, nearly snarling. "All right, listen, pal. If you know who I am, then you should know I'm the embodiment of loyalty."

Loki examined his fingernails casually. "It might have been mentioned, yes."

"Then you should know that no matter what, even if I'm stuck here my entire life, even if I start to make friends and a life here, I will never stop trying to get back. I will never, ever stop fighting tooth and nail for my friends, and for my home. You got that?"

She was practically on top of him now, but he only smiled smugly. "Oh, I very much doubt that."

She opened her mouth to retort when a flicker of gold caught her eye in the edge of her vision. The scepter!

By the time she'd realized what was happening, it was too late to do anything. Time seemed to be moving slowly, as the scepter drifted towards her at an agonizingly slow pace, but it was still happening quickly at the same time and she couldn't do anything and-

Clink.

The reactor. Tony had gotten so used to it that Rainbow, with his memories, hadn't thought about it once the whole time she'd been him.

Clink. Clink.

Loki scowled. Wow. First show of emotion I've seen out of the guy. Probably not a good thing, though.

She shrugged. "Product malfunctions, huh? It's a normal part of the business world, don't sweat it." A small part of her noted how much she sounded like Tony. She was getting better about that.

But in her anger, she'd underestimated him. His human appearance made her forget that he was one of a race of strong and nearly immortal aliens. Now, as she was lifted with ease off the ground, she realized her mistake in goading him. "Uh, Jarvis? Could you deploy the new suit? And hurry?"

Then Loki threw her out the window.

"JARVIIIIIS!"

She heard the loud WHOOSH of the suit flying through the air and the metallic whirs as it scanned her armband, but the ground was getting closer. Hurry hurry hurry...

It hurried. The familiar clicks of the suit wrapping itself around her rang out, sounding loud in her ears. As she spread her hands to catch herself, just feet above the ground, she mentally thanked Celestia that Tony had seriously upped the speed that the new suit came onto him.

Loki stepped out onto the landing platform. Her fists clenched, ready to fight-

-and a bolt of lightning flickered across the sky as a figure in a red cape slammed into him, knocking him to the floor.

Her face broke out in a huge grin of relief. He's not dead after all! And if that's the case... maybe Banner's not dead either? She only allowed the hope to fill her for a moment, however. No use setting up for disappointment. And now that Thor was handling her job of distracting Loki, she could take a few minutes, see how the evacuation was going, check on the tesseract again. It almost sounded relaxing, after that mess on Tony's tower.

She streaked into the air, gaining altitude until she was near the level of the top of the tower. The entire city was spread out under her--and she didn't like what she was seeing. "Jarvis? This evacuation isn't going to work. We'll need to..." She thought for a moment. "We need to get the people closest to the tower out first. I think they'll have to go on foot, this traffic won't clear up any time soon. If we hurry, we might get several blocks. Then we'll just have to try to contain whatever the heck happens here to as much space as that gives us. Send the message to, I don't know, the police? Who's in charge of evacuations here, anyway?"

"Technically, the mayor, but the police are overseeing the evacuation and are more likely to be able to change it on such short notice. Message sent."

She nodded and turned towards the tesseract, but before she could move, Jarvis sounded in her ear again. "You aren't Tony, are you?"

Uh-oh. The suit had anti-theft devices that would kill her easily if she made the wrong move. "What do you mean?" she asked, trying to stay calm.

"Your behavior's been a little odd all day. Then, when you were talking with Loki, he called you 'Rainbow Dash', and both of you referred to this not being your home. You said 'heck' instead of anything stronger. And you asked 'who's in charge of evacuations here', as if it was somewhere other than where you're from. Yet you knew where to find the wristband, you look like Tony, and even your genetic makeup is identical to his. In fact, your fingerprints are the same, and even identical twins have different fingerprints. So, what's going on?"

Excuses and explanations flashed through her mind, each less plausible than the last. She swallowed hard. "Um, kind of Tony. Kind of not."

"Explain."

How could a voice belonging to a literal robot send such chills down her spine? "I'm not completely sure what happened. I have Tony's memories, but I'm not Tony. My name, like Loki said, is Rainbow Dash, and somehow I'm in Tony's head, and he's probably in mine, which is almost certainly working out extremely poorly and I'd very much like to get back home and switched back, but this world is in a bit of a crisis and even though it's not my home I feel like I should do something, so can we focus on saving the world and work out the details later?"

There was a long pause. Finally Jarvis asked, "Did you breathe at all during that sentence?"

"Nope. Does this mean we're good?"

"For now. I hope you can fight as well as Tony can."

"Me too."

Rarity sighed with relief as New York came into sight. Piloting the Quinjet was certainly a thrill, and she had all Natasha's flying knowledge, but it would be a relief to get her feet on solid ground again.

A beam of brilliant blue light shot from the roof of Stark Towers, illuminating the sky. "Looks like we're out of time," she murmured. This was about to get tricky.

"We've got a perimeter for a few blocks," Tony called through her comms. "I'm not sure exactly how far, but we've got to keep these guys away from civilians."

Black dots poured from the portal opening in the sky. As she grew closer, two smaller red dots came into view, taking down many of the black things. Closer still, and they began to resolve into strange shapes, somewhat like motorcycles. She took a deep breath, summoned all Natasha's knowledge and skill, and started gunning them down with the gun on the bottom of the jet. It didn't last for long, though; purple blasts ripped through the hull and wings, and the plane faltered. She managed to bring it to a decent landing, but there was significant turbulence, and it skidded on the ground, making a terrible shrieking noise.

She, Clint, and Steve spilled from the plane, all feeling relieved to be back on the ground. Tony and Thor were spiraling around the stream of motorcycle-things, driving them towards the ground to meet the others. Clint seemed to be borderline panicking. Rarity couldn't blame him; he and Natasha had both seen many things, but whatever was pouring from the portal was weirder than most. Still, he got a good vantage point on a roof and started shooting, felling plenty of motorcycle-things. Steve and Rarity didn't have to wait long to get a look at the things themselves; they were being funneled towards them at a mildly alarming rate. As they swooped down, Rarity finally got a look at what they were fighting and desperately wished for her fainting couch.

Aliens.

There are ALIENS in the CITY and it's MY JOB to deal with them because I'm Natasha and WHAT IN EQUESTRIA AM I GOING TO DO?

And then the battle was joined.

Equestria: If at First You Don't Succeed...

Discord laughed and teleported away. Tony, who had caught himself with his wings, watched the other ponies pick themselves off, struggling to untangle the heap they'd landed in. They dusted themselves off and looked around. Nopony seemed to have anything to say. Tony was pretty sure he knew what they were thinking, though: What happened? Why didn't it work? What did Discord do?

Applejack spoke first. "Excuse me fer a minute. Rainbow, Ah need to talk to ya, alone."

Confused, Tony followed her a distance from the group. He could feel the stares of the others on him, wondering what Applejack was doing. Did she know he wasn't Rainbow? Did she blame him for the failed attempt to use the Elements? How would she react if she thought he was an imposter? Would she try to attack, or would she talk first? Would she accept his explanation? If it came to a fight, could he take her? What about the others? If all else failed, he could simply run away. Or fly away, that is. Only Fluttershy could chase him in the air, and there was no chance she'd catch up. Then, of course, the Princess would be alerted, and whatever energy could be spared from the Discord situation would probably be spent tracking him down, and the whole thing would be pretty terrible.

All these thoughts went through his head in a fairly short time, before Applejack even started to speak. By the time she opened her mouth, he was very on edge, his muscles tensed in preparation. "When the magic faded out," she said, "it didn't cut off all at once."

"It... didn't?"

"Nope. The fading started in one place. That one place was you."

His heart thudded loudly in his chest. Applejack stepped closer. "And Ah think Ah know why. Yer not Rainbow Dash at all..."

PANICPANICPANICPANIC-

"...are ya... Tony?"

His mind blanked, then started racing faster than ever. "How- what- who-"

"Ah'm Steve."

Tony blinked a few times, then started laughing.

"What?"

"Captain America... with a Southern accent... oh, it's too hilarious."

"Can we focus, please?"

He sat bolt upright. "Capplejack."

"We are not calling me that!"

"We are totally calling you that."

"Maybe ya should focus on the creature of chaos intent on destroying this entire world."

His mind was still racing, connecting dots. "Hold on... if I'm the cocky, brash one, and you're the one with as much integrity as the entire state of Texas, honest to a fault..."

"What?"

"Think about it. Who else is here? The incredibly scientific nerd. The feminine one, who's also manipulative. The exuberant one. The shy one."

"Oh my goodness."

"We need to get you some swearing vocabulary," Tony muttered, taking off back for the main group. "I figured something out," he announced, on arrival.

"What?" Twilight asked. (Though a little hesitant--almost like someone not used to being the leader of a team?)

He pointed to her, Pinkie, Rarity, and Fluttershy, one by one. "Banner. Thor. Romanov. Barton. Correct?"

None of them acted like he was spouting nonsense. Not one of them asked, "What even are those words?" Instead, every one of them nodded.

"Yes! Four for four!"

Capplejack, who had joined the group by now, said, "That's great that we've figured that out, but... what do we do now?"

The silence stretched out painfully. Finally, Twilight--Bruce--admitted, "I don't think there's anything we can do. You saw what happened out there. The Elements don't work for us. The only thing that would help would be if we could get the original Bearers back, but how would we do that?"

"And if they come back, what'll happen with the Loki situation on Earth?" Natasha added. "They probably replaced us just like we replaced them, and if we bring them here somehow, Earth will be unguarded."

"If it comes down to saving Equestria or saving Earth, I think I'd have to choose Earth," Clint said, in Fluttershy's soft tones.

Steve looked like he wanted to object, but instead, he merely said, "It probably won't come to that. An' if it does, we probably won' get ta choose anyway. We don't have a way to get back to Earth, we don't have a way to get the Element Bearers back here, and we don't have a way to switch bodies. There's no use worryin' about what we can't fix."

"Then what do we do?" Tony asked.

"I was gettin' to that. Natasha, do your thing. Get Discord to gloat, so that he slips up and reveals something. Bruce, Twilight can pull the answer to just 'bout everything out'a that library. Tony, Thor, Clint, and I will work on keepin' the effects of the chaos from killin' somepony. I doubt even the Elements can reverse that. Got it?"

They saluted and galloped off in different directions.

Earth: Coming Together

Twilight rolled into a thriving battle on a motorcycle. She was kinda terrified, but it was just like her fight with Nightmare Moon: she had important knowledge that could save the day, and she was the only one who could use it. The world was in danger; she had to do something.

Natasha looked up at his approach. "There's Banner! Cover us!" she called to Steve, then ran to Twilight without waiting for a response. "You're alive! Are you here to help?"

"No, but I figured out how to stop the tesseract." Natasha gaped, and Twilight continued, "I planned to do it before it opened, but I think I still can. It's a matter of resonance--something with a similar frequency is better at cancelling out-"

"What do we need to do?" Natasha interrupted.

"Right, sorry. The scepter, Loki's scepter. Just touching the tesseract with it should be enough, but I'm not sure."

She nodded and touched her ear. "Bruce thinks Loki's scepter can close the portal. Does anyone see it?" Twilight couldn't hear the response. "Gotcha. I'm on it." Without further ado, she turned and sprinted away.

She watched her go, trying to think. What if that doesn't work? What's another way we can close it? Steve barely reached her in time to shield her from falling rubble she'd barely even noticed. "Thanks," she panted, a little breathless from her close scrape. "I really- DEAR CELESTIA WHAT IS THAT THING?"

Steve didn't notice the epithet she'd chosen, probably because he was so distracted with the creature that had appeared in the sky. It moved like an eel through water, but it was moving through the air. She mentally called it "skyworm" because everything needed a name, even giant flying alien snakes of death. She had no idea how it was flying, but guessed it was probably something similar to Iron Man's propulsion devices.

"Doctor Banner?" Steve said from behind her. "This seems like a really good time for you to get angry."

"No- I can't- I-"

The skyworm was charging her. Steve grabbed her wrist and dragged her to the side, the massive creature missing them by inches.

"We could really use the Hulk right now!" he shouted, blocking a blast of some kind of purple light.

"No! You don't need a green monster that's just as likely to attack you as he is to attack those things! You need someone who can figure out how to deactivate the tesseract!"

"First of all, you'd have a much higher chance of hitting those guys, simply because there are way, way more of them. Second, didn't you already find a way to close it?"

She ducked as a flying-alien-motorcycle went whirring low over her head. "Yes, but what if it doesn't work? I need to have something else planned! And another plan in case that one doesn't work! And if I become the Hulk, I won't even know if it worked or not! I have to be me, I have to have my brain, so if the portal doesn't close I can find another way! I need to-"

Steve shushed her. "Bruce. Listen to me. It will work."

"How can you know that?"

"Because I know you. And I know that you're not going to be wrong, not about something as important as this. And I know that as the Hulk, you'll tear through those aliens like paper. If you go into it deliberately, you will have control. It's all the difference between falling into a pool and diving off the diving board. Bruce, I trust you. I trust you to be right, I trust you to be able to maintain control. Do you trust me?"

She hesitated. Did she? "Yes. I do."

"Then let go."

A memory flashed through her head.

Let go.

Are you CRAZY?

No I ain't. I promise you'll be safe.

She swallowed hard. "You know, you remind me a lot of a friend of mine."

Then she took a deep breath and allowed rage to fill her. Rage about library books with ripped pages or drinks spilled on them, books returned late and overdue, books that sat on shelves and looked nice, but were never read. Everything that made her most angry filled her brain, and she began to swell.

I'm losing myself! I can't do this!

She wanted to grab onto the thread of herself, or of Bruce, that remained. She wanted to cling to it. But she couldn't do that.

She let go.

Applejack stepped back several steps as Bruce Banner became 'The Hulk'. She did trust him to handle it, but it was still disturbing, watching that happen. The green creature looked up at the skyworm, the animal the size of a train, approaching at the speed of a train. Applejack prepared to run. There was no way even the Hulk could stop something that big, that quickly.

A green fist met the creature, right in the center of its face.

It shuddered to a halt.

Applejack didn't stick around to watch the rest of the conversation. She'd been slacking off chatting while the rest of the battle raged on; it was time to kick some alien flank.

Rainbow Dash couldn't deny that this battle was pretty awesome, but even she was starting to get tired--and so was her suit.

"Power at 10% capacity," Jarvis warned her.

She looked up at the sky. "And they're not even slowing down." Then her eyes flickered with the light of a sudden idea. "Remember two days ago, when I fought Thor?"

"Yes, but what- oh. Oh no."

"Hey Thor! Hit me!"

WHAM.

"IIII MEAAANT WIIIITH LIIIGHTNIIIIIING!" she called as she flew through the sky.

"Then why didn't you just say so?" Thor demanded, flying after her. A crackle filled the sky, and suddenly electricity was surging through the suit and across her body. She'd known it would hurt, but it was still all she could do to keep from screaming.

"Power at 350% capacity," Jarvis reported.

"Good, 'cause that hurt a lot."

"Guys?" Clint asked through the comms, so softly Rainbow could barely make him out.. "I'm out of arrows. Now what?"

Rainbow paused to spot his location. "Hold tight, I'll come pick you up."

"Uh, how literally do you mean that?"

"Very!"

"Wait!"

She didn't.

"Aaaaaaaaaaaaaaaaaaaaa-"

"Where do you want me to leave you?"

"-aaaaaaaaaaaaaaaaaaaaa-"

Shrugging, Rainbow dropped him near a building. "You can hide out in here. Probably in the basement." She'd barely finished talking before he scampered inside. "Huh. Well, fighting isn't for everyone." She kicked off into the air when Fury's voice sounded in her comms.

"Tony, you've got a nuke incoming."

"A WHAT? You can't be serious!"

"Yes I can. The Council wants to cut our losses before the invasion overwhelms all of you." A picture of the position and velocity flickered onto the screen on Rainbow's helmet.

There are still so many people here. I promised I wasn't going to let anybody die. If she put it underwater, would that keep it from going off? If it went off anyway, would it destroy the city, or "just" poison the whole ocean with radiation? Would that be better? Maybe she could send it through the portal and destroy some forces there. The fallout, and maybe the explosion, would still hit the city, but it would do a lot less damage. Okay. If it'll explode when it hits the ground, I can drop it in the ocean so it doesn't impact anything hard enough. If it's a timer, or altitude trigger, I'll send it through the portal. That'll minimize the damage.

"Will it explode by a timer, an altitude trigger, or impact?"

"How should I know what kind of bomb they sent?" Fury demanded.

Rainbow groaned, trying to think, when yet another voice entered her comms. It was Natasha. "I can close the portal, can anyone copy?"

Perfect! She could send it through, then close it off before the explosion. "Hold it open a little longer."

"Tony-"

"No time to argue, we've got a nuke. I'm gonna send it through. Then close it--fast."

"All right, but hurry!"

Thor's voice entered the helmet now. "Let me do it."

"Huh? Why?"

"Just trust me. Close it as soon as I go through. Don't wait for me."

"No! Thor, you can't-"

"Yes I can. Trust me, Rainbow. I have to be the one to do this."

Thor whooshed past him, scarlet cape flapping in the wind. Rainbow fought down a lump in her throat. Every inch of her was screaming, No! Stop him! You can't let him die! You promised yourself nobody would die! You have to DO SOMETHING!

But he had chosen this. And he had told her to trust him.

He came flying back the other direction, one hand holding Mjolnir, the other steering the nuke. Something wiggled at the back of Rainbow's brain. Something was strange. But he couldn't figure out what it was.

She turned and followed him to the portal, taking down a few alien motorcycles halfheartedly along the way. She was still missing something. Something wasn't right, didn't make sense.

The nuke! He's never seen a nuke, how did he know what to grab?

Another part of her replied, It wouldn't have been hard to spot the big grey thing flying towards the city and assume that was it.

Fine, she conceded. But there's something else... I just can't put my hoof on it. Or my finger, I guess.

He shot through the portal. Natasha, swallowing hard, jabbed Loki's scepter onto the tesseract. The portal cut off abruptly, and the aliens suddenly powered down. Some kind of signal from the other end must have been keeping them going, and the portal's close had cut it off. That, or Thor had hit whatever was sending it. Maybe both.

She sniffled as she landed next to the rest of the group. I knew all along, you can't get through a conflict on Earth without casualties. Tony's known that since he was a kid. How did I delude myself into thinking we could all make it out of this okay?

They stood there in silence for a long moment. Rainbow wished that at least that feeling of something she couldn't put her finger on would go away. It kept eluding her, and she wondered if it was something that could've saved Thor. Had she been inches from figuring out a way that Thor would make it? If she'd figured out what it was sooner, would Thor be here right now?

Part of it clicked. He called me Rainbow. HE CALLED ME RAINBOW!

"Hey guys! Did I miss anything?"

She whirled around, jumping feet in the air. Thor was sitting there right behind her, looking casual. And suddenly she knew. She realized what she hadn't been able to put her finger on.

"...Pinkie Pie?"

"You betcha! Sorry it took so long. I had to wait a while before I showed up, to make sure there was proper comedic timing."

"I- but- what?"

"I can only do it if it's funny, silly!"

Rainbow blinked as yet another realization slid into place. "Wait. Six of our friends, six of this team... we all got brain-swapped, didn't we?"

"Yeppers!"

"You gotta stop saying Pinkie Pie-ish things in Thor's voice, it's weirding me out. Also, you knew this whole time?"

"You didn't?"

"Well- I-"

"Eeexactly."

"What?"

Pinkie plowed on as if there had been no interruption. "Now come on! We need to go get Loki, and then we can use the tesseract to go home!"

Use the tesseract to go home.

She could barely even process the words. All the hope that Loki had dashed flooded back into her. Her friends were by her side, they'd all made it out alive, and they had a way home! "Let's go!" she shouted, taking off at lightning speed.

"Hey, wait!" Captain America called behind her. "Not all of us move that quickly!"

She didn't even notice.

Author's Note

Starting to wrap up! Woo!

Equestria: ...Try, Try Again

Bruce trudged up the staircase of the Golden Oaks Library, head hanging. They'd failed. They'd failed so badly that the only way to reverse it was to try to get someone else to come in and fix the problem. Bruce didn't like it one bit.

And worse... what if the ponies they were trying to get to were having the same trouble with the situation back home? What if they couldn't handle Loki any better than the Avengers could handle Discord? The thought turned his trudge into a full-blown gallop up the stairs. He was pretty sure the books about other worlds had been shelved here after Twilight's last Reshelving Day. He wasn't positive, though. Even Twilight couldn't keep track of her various organizational schemes. The only one who could was Spike... who was probably also upstairs, in the bedroom.

Wait a second. Spike. What on earth would he tell Spike? Or Princess Celestia? The thought made him wince. Explaining to a baby dragon who looked up to you like a parent, and an immortal ruler of near-limitless power, that you weren't who they thought you were and you'd failed the task they'd set you... that sounded like a pretty bad day to Bruce.

As he stepped onto the landing, he heard a groan and saw Spike lying on the floor, arms over his belly. "Spike! Are you all right?" A stomachache. Could be nearly anything, the flu, or food poisoning, or... His gaze swept the room, taking in the piles of scrolls. ...or receiving too many letters in a row.

"The Princess... has been sending these... since I got back!" Spike gasped. There was a whoosh of green light, and another one materialized in thin air. Bruce caught it in midair (From across the room! Did that ever get old for unicorns?) and unrolled it. The handwriting jumped out at him. He- or rather, Twilight- had seen it over and over again. Spike had written this. Dear Princess Celestia...

He skimmed it quickly. It was the letter Twilight had written about Rarity's experience with the Diamond Dogs. He checked the bottom, margins, and back for any notes from the Princess, any explanation for why she'd sent it, but it was blank. "I don't understand."

Spike said nothing, too busy coughing out another letter.

Bruce steadily made his way through the pile, even with Spike's frequent additions, reliving memory after memory that weren't his. Finally he reached the bottom, but he'd gotten no farther than before. He still didn't understand.

And then suddenly, he did.

Somehow, by reading the letters, by reliving Twilight's most important memories, he'd actually become more Twilight than he was when he started. Maybe, just maybe, he was even Twilight enough to use the Elements.

Quickly he grabbed a quill in his magic and scribbled a quick note.

Dear Princess Celestia,

Thank you for sending back the letters. It was exactly what I needed. However, it's taking a toll on Spike, and now that the letters have done what they needed to, you can stop sending them. Thank you.

Your faithful student, Twilight Sparkle.

"Here, Spike, send this. It'll be the last one, I promise." He groaned slightly, but complied. "Now I need to go back out there, and I need you to stay here. I'm sorry about that. Just know that your passing of messages played a very important role in defeating Discord."

Bruce left the little dragon recuperating on the floor as he picked up the entire pile of scrolls and galloped back down the stairs. As he went, he unrolled each scroll and read it, then moved it to one side. Soon he was holding seven different piles of scrolls. It was a bit of an intense magic workout, but nothing Twilight's power couldn't handle.

As he exited the library, he sent up a blast of magic like a beacon, a blast colored purple and pink. Twilight's colors. Hopefully that would be enough of a signal to imply to the others, "Guys, I found something, come here," and also to show who had sent it.

To absolutely no one's surprise, Tony was the first to arrive. He blasted in, leaving a rainbow trail, and Bruce shoved the largest pile of scrolls towards him. "Read these while we wait for the others. I'll explain when they arrive."

"Well, okay." He picked one up, unrolled it, and began reading. As others arrived, they too received a pile of scrolls. Once they'd all assembled, Bruce stood up and cleared his throat.

"Princess Celestia sent back the letters I sent her, about the lessons we all learned. After reading them, I actually became more like Twilight and less like Bruce."

"Is that a good thing?" Tony objected.

"Well, I think so. At least for now. So I picked them up and organized them into piles for who they'd be more important to. Those ones are Rarity's letters, those are Fluttershy's, and so on. The pile Tony has is the letters that apply to everyone, so all of you will need to reread those before it's over."

Tony laughed. "You really are more like Twilight!"

"Efficiency isn't reserved to just Twilight," he grumbled, as the sun dropped abruptly below the horizon and the moon popped up. Quickly he lit the brightest light he could so they could keep reading. It took seven five-minute day/night cycles for them to finish.

"Did it work?" Tony asked uncertainly.

"Only one way to find out." Bruce looked at the assembled group and smiled. "Let's go kick some draconequus tail."

They found Discord sitting on a weird throne made of swords. As they approached, he conjured up a paper cone and scooped a cotton candy cloud into it. Then he at the paper, transformed the cotton candy into a bright purple frog, and tossed it aside. It hit a twisted and deformed tree made of what looked like glass, where it let out a loud quack.

When they reached the foot of the large blue-and-yellow checkered hill his throne rested on, Discord looked at them. "Ah, is it time for round two?" He leaned back and yawned. "Why bother? Nothing's changed." A frilly sleep mask appeared over his eyes as he spoke, and he transformed the chair into a recliner and leaned back. Little Z's floated over his head.

The Avengers looked at each other and nodded slightly. Bruce focused as hard as he could, and slowly but surely, they lifted into the air. The gems glowed brilliantly on their necks.

Discord sat up abruptly. "What? But that doesn't-"

"Make sense?" Tony asked. "Oh, what fun is there in making sense?"

The light from the Elements was so bright it was impossible to look at. A brilliant rainbow shot into the air, twisting into a spiral before plunging towards Discord, like a tsunami cresting.

"NOOOOOOO---"

There was a whooshing sound, like a rush, and a brilliant wave of light. Their feet hit the ground, the light faded, and slowly, they looked around them. Directly ahead, in front of a once-again-orderly Ponyville, stood a marble-white statue of Discord, a look of shock still frozen on his face.

Earth: Going Home

Twilight knocked on the office door. "Director Fury? We need to talk to you."

There was a deep sigh from within, then footsteps. She felt her heart pounding wildly. How would he react? Bruce hadn't interacted with him a lot, but from the memories of the times he had, her impression was of a hard and determined man who didn't like surprises.

"Maybe we'll get lucky," Rainbow whispered. "Maybe he'll be Celestia."

Before Twilight could respond, the door swung open. "Come on in," Fury said, gesturing inside, "but if this is about the weapons I already told you that wasn't my idea."

"It's not about that." Twilight took a deep breath, trying to compose herself and explain. "It's... well, I'm not sure how to explain this, but-"

Pinkie jumped in. "We're actually horses from another world but our brains got switched with your Avengers and it was us taking down Loki yesterday, not them, and now we need the tesseract so we can get home to our world and switch back and then you'll get your actual Avengers back!"

"Concise," Rainbow approved.

"Thanks!"

Fury shook his head like a dog ridding itself of water. "Say that whole thing again, but slowly."

"Weeee're aaactuuuallyyyyyy..."

"Just let me," Twilight interrupted. "Director Fury, we're not the Avengers. We're... people... from another world, whose minds somehow ended up in their bodies. We're pretty sure they're in ours. We need you to lend us the tesseract so we can go home, find the actual Avengers, and switch back."

"Wow. Just as concise, but also way easier to follow."

"Hey!"

Fury rested his head on his hands for a while, thinking about something. Finally he muttered something about the Council, and a word Twilight would never, ever use. Then he stood up. "All right, follow me."

They walked down to the basement of the SHIELD facility and arrived at one of the highest-security areas any of them had ever seen. Fury scanned his eye, the palm of his hand, and his whole face, then entered a very long passcode. The door slid open smoothly, revealing a small vault. The tesseract stood alone on a stand within.

Without a word, Fury turned and walked away. "Where are you going?" Rainbow called after him.

His voice echoed back as he rounded a corner. "Somewhere with plausible deniability."

Twilight shrugged, then opened the bag she was carrying and examined its contents. "All the science books I can carry... check. Rainbow, do you have the blueprints for the Iron Man suit?"

She waved a handful of papers. "Stayed up all night to get all the details from Jarvis. I should be able to recreate the whole thing."

Twilight swung to Rarity. "Design ideas from Earth fashion and the supersuits?"

"Check!" she sang, waving a small notebook.

"Was anybody else bringing anything?"

Fluttershy and Applejack shook their heads, but Pinkie jumped up and down, lifting a giant bag into the air. "I got TEN POUNDS OF STREAMERS!"

"Pinkie, you already have lots of streamers!"

"Yeah, but these are Earth streamers!"

"But- but they're exactly- you know what? Never mind. Are we ready to go?"

Pinkie Pie gave a huge gasp. "Wait! I almost forgot!"

Rainbow rolled her eyes. "What now?"

"Quick, everyone look at that guy!"

They turned, following her pointing finger to a stranger walking past. He was short, with a round face, white hair, and a mustache. "What's he even doing here? Why did we need to look at him?" Twilight asked.

"Obligatory Stan Lee cameo!"

"THAT EXPLAINS NOTHING!"

Pinkie pulled a glass container from somewhere and scooped the tesseract into it. "Everybody touch me!"

They complied, and she twisted one side. There was a flash of light, and then they were gone.

Equestria: Arrivals

"Princess Celestia?"

"Yes, Twilight?"

Bruce fidgeted. "...How did you know to send those letters?"

"I believed Discord was likely to do something that made you unable to use the Elements, and you might need to be reminded of who you really were." She glanced down at his disappointed face. "Why? Was I wrong?"

"Not quite... I just hoped you had known a little more specifically. Would've made the explaining easier."

Her face grew concerned. "What did Discord do? What happened?"

Bruce took a deep breath to explain.

There was a blinding flash of light and a loud whoosh.

Bruce blinked, his eyes readjusting to normal light levels. Six bipedal figures started to resolve. Tony, as usual, was the first to recover. "You guys really need to work on your timing!"

Celestia had stood up, and her horn was glowing threateningly, but at this she glanced over. "You know them?"

"I mean, sort of?"

"Are they a threat?"

"No!" Bruce exclaimed hastily. "They're... us."

Applejack and Steve (in each other's bodies, of course) stepped forward to explain at the same moment. "Oh, go ahead," Applejack offered.

"Nah, nah, you first."

"No, really, go ahead."

"Oh my goodness, I'll just go." Tony flapped up to join the Princess. "They're from another world and our brains got swapped."

"Concise," Pinkie complimented.

"Thanks."

Princess Celestia maintained composure. Thousands of years of bizarre shenanigans will do that to you. "I know a spell that will switch you back. Stand next to the person you were switched with, everypony. Everyone, I suppose."

"Don't worry, darling, that confused all of us," Rarity said, moving to stand next to her body.

"Anybody else think it's really weird seeing your body from the outside, or is that just me?" Tony asked.

"Pretty sure that's all of us," Applejack said.

The more intensive a spell is, the brighter your horn glows when you cast it. Celestia's horn glowed with the light of the sun, and everyone had to look away. Twilight privately thought it was probable that only an alicorn could cast a spell like that. Two yellow orbs floated out of her horn, connected by a thin line. They moved to the closest pair, Steve and Applejack, one orb floating over each head, still connected to each other.

Then the spheres touched.

Bruce could feel what was happening with some magical sense of Twilight's. It was like lightning; the consciousness of each individual pulled out of their body and zapped across the line into the other head. It happened faster than blinking. Princess Celestia didn't falter, but moved immediately to the next pair. By the time she'd finished the third, she was gritting her teeth to keep going. By the fifth, she closed her eyes to keep concentration, and pain was written in every line of her face, but she didn't stop.

Finally, she finished the last pair and immediately sunk to the ground. Twilight ran over to her. "Princess Celestia! You shouldn't have pushed yourself so hard, you should've taken a break, are you okay?"

She smiled at her student. "I'm fine, Twilight. I'm just tired. I haven't pushed myself like that in a while, but the exhaustion should only last for another hour or two."

Twilight noticed that she could no longer distinctly recall everything from Bruce's past, just the things that had happened while she was there, with a vague knowledge of his general life. She also noticed that she didn't have any memories from the time when Bruce was her--she had no idea what he'd been up to in that time.

"Before you guys take the tesseract back to Earth," she suggested, "we should probably catch each other up on what happened while we were away. There's a great cafe just down the street--we could go there for an hour or two, chat, and relax."

Tony shrugged. "Sounds good to me, but won't they all freak out a little, seeing us?"

"Honestly?" Twilight laughed. "They've seen weirder."

Author's Note

And that's a wrap!
...or is it?

After-Credits Scene 1

Twilight stumbled through the portal. As she tried to clear her dizziness, she heard Spike's voice crying in surprise. Did he come along? I don't think he was supposed to come along!

She looked over at him and gasped. "Spike? Are you... a dog?"

He turned in a circle. "Um, I think so. But I have no idea what you are!"

She raised her hooves to examine them--but they weren't hooves. They were hands.

No no no, not again, I'm a magicless human AGAIN are you KIDDING ME-

Twilight screamed.

After-Credits Scene 2

It was book-sorting day in Twilight's castle. Again. Starlight was working on one end of the room, Twilight on the other, when suddenly a very familiar whooshing noise resounded. She dropped several books. Is it them? Can it be? It's been ages, though!

"Excuse me, do you know where we can find a mare named Twilight Sparkle? Purple unicorn?" That was Tony's voice, all right. She spread her wings and took off. "We were trying to get to her library, but we seem to have-"

"Who are you people?" The sound of a shimmer of magic, Starlight charging a spell. "What do you want with Twilight?"

She landed with a thump. "Don't worry, Starlight! They're friends!"

"There you are!" Steve sounded relieved. "It's weird, I thought we were going to your library, but we ended up in this crystal place and WOAH YOU GOT WINGS WHEN DID THAT HAPPEN?"

"Who's the new kid?" Natasha added.

Twilight sighed. "This is my library now, in my castle-"

"Your what?"

She took a deep breath. "I'm an alicorn now, my brother married another alicorn, they had a third alicorn baby. Discord got reformed. The Cutie Mark Crusaders, Rarity and Applejack's sisters plus another filly, got their cutie marks. This is Starlight, she almost broke time at one point but then she realized she was making a mistake and now she's my friendship student. Oh, and I have this castle. THIS IS WHAT HAPPENS WHEN YOU DON'T VISIT FOR THREE YEARS!"

Tony's eyebrow raised. "Anything else?" he asked mildly.

"Lots, but I'm guessing you don't have time for all of it. Since you took so long to visit, the only reason you'd show up now is if you have some huge crisis going on and need our help."

"Got it in one!"

"Somebody-" Clint glared at Tony- "thought it would be a good idea to build a super-advanced robot, and now he's trying to destroy the world."

"Tony, or the robot?"

"Hey!" Tony protested.

Twilight sighed. "Give me an hour or two, I can get everypony together. But won't the humans freak out when they see us?"

Natasha grinned. "Honestly? They've seen weirder."

Author's Note

For clarification, this takes place in the middle of Season Six.
Also, I'm not doing an Age of Ultron sequel. I might do one for Infinity Wars, though, depending on how much it inspires me. Look for Elements of Infinity a while after the movie--like a year, probably, since it takes me forever to get my lazy fingers onto the keyboard. Anyway, this has been a fun ride. I hope you all enjoyed.

Prologue: So Discord and Loki Walk Into a Bar...

A cheerful voice appeared without warning in Loki's mind. "Hello there!"

Loki grit his teeth. Mentally. "It is generally considered rude to manifest in another's mindscape without invitation."

"Ah, yes, rules of basic decency. So boring. You should be glad I didn't completely overwrite you to be the exact opposite of yourself!"

A little more wary. "...you can do that?"

"Oh, please." The voice sounded as if it were waving its hand flippantly, which it wasn't, because it was a disembodied voice. "I can do anything."

"And what," Loki asked even more warily, "do you want with me?"

"Well, you see, it suddenly occurred to me that both of us are facing a team of six who could be our undoing, and so I thought, why not swap?"

"...Swap."

"Swap! I'll replace the minds of your 'Avengers' with the minds of my 'Elements of Harmony'. They'll be too confused wandering around in their new bodies and abilities to be able to stop us." The voice chuckled. "Better yet, they won't know that the entire team has been replaced. They'll be desperately trying to act like their real counterpart, afraid of the conclusions others will jump to in times of crisis like this. It'll be just so much fun!"

"If you can really do anything, like you say, then why can't you just vanish both pairs out of existence--or turn them into opposites of themselves." His mental voice dripped with sarcasm.

"Oh, I could. Easily." A bored tone that sounded as if the voice's owner was examining his fingernails. "But really, this will be just so much more entertaining!"

"Hmph. I suppose so. And what if I refuse your offer?"

"Hmm?" Hysterical laughter. "Oh, that's adorable! You actually think that I need your consent for this!"

And on that disconcerting note, Loki was alone in his mind again.