AU August is an event that happens every year that I somehow manage to miss consistently despite my best attempts. So in 2021 I made my own custom list of prompts, A-Z, and filled them out at my leisure. (Originally I meant to have 31 prompts, one for each letter of the alphabet and then 5 free days, but I ran outta steam. Ah, well.)

Each day features a different AU, tackled in the 5 sentence fic format - no entry can be more than five sentences long. They also, obviously, are self contained, and can be read in any order.

Have fun!

Fandom: Rise of the Guardians
Type: 5 Sentence Fics
Pairings: varied

1. "A" - Astronaut
2. "B" - Babysitter
3. "C" - Coffee Shop
4. "D" - Detectives
5. "E" - Elementals
6. "F" - Future
7. "G" - Groundhog Day
8. "H" - Halfa AU (Danny Phantom Crossover)
9. "I" - Immortals
10. "J" - Jumanji
11. "K" - Kitten
12. "L" - Library
13. "M" - Mermaid
14. "N" - Necromancy
15. "O" - Office
16. "P" - Photographer
17. "Q" - Quarantine
18. "R" - Royalty
19. "S" - Soulmate
20. "T" - Tattoo Artist
21. "U" - Undercover
22. "V" - Vampires
23. "W" - Wings
24. "X" - X-Men
25. "Y" - Yeti Uprising
26. "Z" - Zombie Apocalypse


1. Astronaut

This, Jack Frost thought, desperately trying to cling to the last dredges of his sanity; this was not covered in my astronaut training.

Around him, the barren landscape of Earth's moon stretched in all directions, white and dusty and dotted with craters, a place Jack had spent his lifetime studying, hoping to someday earn the right to visit, to experience, to step out of his shuttle and leave his footprints in the moon dust.

Except the surface wasn't barren—when the shuttle touched down, and Jack stepped from the spacecraft, there was already a little man here, waiting.

No space suit, just a white tie and pants and fancy jacket, and a round face that seemed to reflect the sun when he smiled, full and bright; the little man raised his arm and held out a—was that a shepherd's crook?—as a welcoming gift, or perhaps as a peace offering.

A couple of quick blinks did nothing to dispel the mirage, (not a mirage, then, some traitorous voice whispered in his head; perhaps just a Man In The Moon) and so, at his wits end, Jack raised a hand to his spacesuit's comm links and announced,

"Uh, Houston, I think we have a problem."

2. Babysitter AU

"Oh thank goodness, there you are, thanks for coming on such short notice," The woman with the green- and gold-dyed hair ushered him in the instant he knocked on the door.

"I—what?" Jack Frost asked, bewildered, because he'd never met this woman before.

"Emergency at the hospital, I'm afraid, I'll be out all night—naptime's at 4, bedtime's at 8, there's money for food on the fridge, and again, this is such a big help, I really can't thank you enough," she barrelled on, handing Jack a key, a blanket, a list of emergency numbers, and a sizable chunk of money.

—And then, in a whirlwind, she was gone, leaving Jack blinking in confusion before he could explain that no, uh, wait a second, he'd just gotten a flat tire in front of her house, and only wanted to ask if he could please use their phone…

Above, lining the stairway, a gaggle of seven kids blinked down at him, chittering to themselves; the oldest, a girl with mismatched eyes, rested her chin on the banister, giving him a knowing look, and in a voice that sounded very wise for her age, asked, sensibly, "…So you're not really our babysitter, are you."

3. Coffee Shop AU

Pitch preferred his coffee black — simple cup, dark roasted, no additives — and so it physically pained him when he had to get a job at the local coffee shop, serving these absolute heathens.

Nicholas North, for example, always ordered a mocha, extra whip, three pumps of peppermint and cinnamon dusting on top… which was better than Aster Bunnymund, the artist, who just straight up asked for hot chocolate whenever he came in.

Miss Iyana, and her girls, always asked for tea, unless there was some sparkly new gimmick drink on the menu to try, and Sanderson, the sleepy-eyed psychologist who dropped in near closing time, always asked for a latte (with art), and always asked for anywhere between 5 to 9 extra shots of expresso.

All of this paled in comparison, of course, to the brat that came in with his blue eyes gleaming, and asked for an iced, ristretto, 10 shot, venti, 4 pumps vanilla, 8 pumps caramel, 4 packets of splenda, shaken, not stirred."

Pitch swore he would murder Jack Frost in his sleep someday… except, with an order like that, Jack probably considered sleep less like a biological need, and more like a boring suggestion.

4. Detectives AU

"Alright, show us the newest vic, Sandy," Aster said to the coroner, as Tooth handed the case files to both him and Nick.

There was a new Serial Killer in town, one who went by the moniker Pitch Black - this was the sixth death in as many days, and the detectives at Guardian HQ would not rest until they stopped him.

"Now, I already ran his dental records," Tooth, from forensics, said, as Sandy pulled back the modesty sheet that covered the boy's corpse, "And I got a hit - this is Jack Frost, age 17, tortured and left to drown in the lake…"

A strained cough broke her monologue, and everyone froze—then looked down.

Blue eyes cracked open as the dead kid, much to their shock, began waking up on the autopsy table; Jack Frost blinked, coughed, and blinked again, but none of his audience dared to move until the the boy squinted up at them, and quietly rasped,

"…where am I?"

5. Elementals AU

The white hair, the blue eyes, the silvery glint at his fingetips—there was no mistaking it, the boy was an Ice Mage, blessed with one of the most rare and powerful magicks the kingdom had to offer, perhaps even more powerful than Aster's own Earth magic.

"But—" how, Aster wanted to ask, brow furrowed and perplexed; "There hasn't been a single elemental born in the kingdom since Pitch wiped them out a century ago…" Everyone, that was, except for Aster himself.

"A century?" Jack scoffed, looking apprehensive yet mischievous all at once, like he knew something Aster didn't.

"Aster," Jack asked at last, eyes darkening with magic, and deep voice laced with the power of thunder, "…Just how old do you think I am?"

6. Future AU

"Look at it, Jamie—we finally got hoverboards," Jack said, grinning as he leaned against the headstone.

The Burgess Skyline in the distance was a vivid neon glow, dotted with silhouettes of people, adult and child alike, freewheeling through the sky on their new hovertech, and Jack sighed, smiling at the sight.

Hoverboards, in Jack's opinion, were just the tip of the iceberg—they paled in comparison to some of the inventions that'd emerged in the last several years, the laser swords, holo-vistas, and butterfly ships, just to name a few—but it was nice to see a long-standing dream finally come true, you know?

"…I just wish you were here to see it," Jack whispered, voice aching.

Jamie's gravestone was firm and steady at his back, the name long worn away, but no matter how long time marched forward, towards the dawning of a new Golden Age, Jack would always find time to look back and remember where it all started, in the quiet bedroom where he first met his first believer - and oldest friend.

7. Groundhog Day AU

It was a time loop, one that had him repeating that nightmare, always waking up three days before that fateful Easter - and for the life of him, Bunnymund couldn't figure out what the hell he was doing wrong.

He failed Easter, and died — beat the Nightmares to the Tooth Palace, and died — took an arrow for Sandy, and died — broke away from the group to face Pitch alone, and died — no matter what Bunny did, Pitch always won, and the timeline reset back to zero, three days before Easter, where no one remembered anything and nothing ever changed.

Except… this time, something did change: Manny spoke up at the meeting.

Bunny didn't know what he could've done to trigger the change, or maybe MiM knew of the time loop all along, and was only acting now, but before he knew it, the crystal was rising from the floor, ready to select a new Guardian to help turn the tide, and hopefully break the static time loop once and for all.

Unfortunately, reflecting on his predicament, Bunnymund had a sinking feeling that he knew who was about to be picked, and so, closing his eyes and clasping his hands, he desperately started to pray:

"Please not the Groundhog, please not the Groundhog…"

8. Halfa AU

The day that Jack Frost fell through the ice… he died, yes, but perhaps not all the way.

Other spirits, the few who knew, called him "halfa" - half living, half dead, a race that had been extinct for centuries. Jack could, when focusing, make himself human—visible, tangible!—but the trade-off was too high a price to pay.

"The other halfas - those who existed before you - they were destroyed," the ice yeti warned, placing a hand on Jack's shoulder that felt kind, "so it's best that you remain hidden, or the dark force that wiped them out might very well destroy you, too."

So for three hundred years, Jack Frost hid, drifting alone in the world… and he might've gone on that way forever, it seemed, if not for one fateful visit on a snowy day to a town called Amity Park.

9. Immortals AU

When Jack Frost wakes up in the hospital, he doesn't know anything about himself except for his name.

The hospital says he's 5'10", 112 lbs, has 20/20 vision and a blood type AB+, and that he's suffering from a rare form of retrograde amnesia. He learns from the nurse that he is a quick healer—"never seen a gash heal up so fast!" she chuckles, nervously—and from the doctor that it's a miracle he even survived the accident, let alone that he came out of it otherwise unscathed.

Everything else, he learns from the tall dark stranger, who appears one day and smoothly guides him away from the hospital's healing gardens and into the back of a car (…wait, is this a kidnapping?) and who, as the vehicle jolts into rumbling motion, sends him an impatient scowl like he thinks Jack is playing some kind of childish game.

"Three hundred years, and you're still pulling this nonsense—why on earth would you let them take you to a hospital?" the stranger demands, and Jack just sits there, dumbfounded, because okay, sure, if he's immortal, that certainly answers a couple questions, but it raises a thousand more.

10. Jumanji AU

"It's… your turn, Jamie," Pippa whispered in a tight voice.

Jamie swallowed, looking down at the yellowed ivory dice waiting for him on the game board.

So far, Pippa, Monty, and Claude had rolled, each time summoning a new horror to their living room—stampeding reindeer, fairy swarms, quicksand—but the rules promised to reset everything once the game was over… so they had no choice but to continue playing Jumanji.

Before he lost his nerve, Jamie swept up the dice and rolled, then watched as the next card materialized in the game board's center:

Children, laughing, don't get lost

or you'll belong to old Jack Frost.

Slowly, the nearby windows started to cloud over with ice, but no one noticed, at first; Jamie was too busy frowning at the card, perplexed, as he asked,

"…who's Jack Frost?"

11. Kitten AU

…So that was clearly Pitch… right?

The cat was sleek and black, and had a piercing golden gaze, too sly to be innocent, too smug to be benign. Baby Tooth squinted as the cat climbed on Jack's shoulders, her arms crossed in protest, because clearly, even if that mangy feline wasn't Pitch Black, it was still obviously up to no good.

"Come on, Baby Tooth, don't be jealous," Jack scolded, as the cat purred and rubbed its face against Jack's jaw; "…he's just a lonely stray looking for some attention, that's all."

Baby Tooth sighed and shook her head—boys didn't know anything, did they?—and quietly resolved to keep an eye on Jack's suspicious new pet… just in case.

12. Library AU

"I'm gonna kill him," Aster growled, his voice carrying over the hushed campus library, echoing off the bookshelves.

"Shh," Sandy scolded, because this was a library, after all.

"68 books," Aster said, pointing at the computer screen in disbelief; "—how does that Frost kid have 68 overdue books already, it's insane!"

Because, Sandy wanted to say, but didn't, because he doubted Aster wanted to hear the truth, he's not coming in to read, he's coming by so he can flirt with the cute student librarian.

The Aussie got his answer regardless, three weeks later, when the books were finally returned—because tucked between the pages, in a rather romantic move, Jack had left a dozen drawings, sketches, poems and love notes, all addressed to Aster.

13. Mer AU

There was a rumor that a mermaid lived in Burgess Bay, but it was one thing to hear the tale, and another to spot the flash of fins disappearing beneath the dock.

Sanderson froze, then scrabbled for his phone, camera up at the ready. Carefully, he knelt, and tilted to peer at the dark waters swirling beneath the wharf.

The Mer's scales were iridescent where they caught the light, a deep blue tinged with green like the coldest of glacial ice, and his face—Sandy gasped, at once dropping his phone with a splash, and almost didn't care, because stars above, he knew that face.

"Oh!" the Mer spun at the sound, startled at first, then smiling wide, the spitting image of the Overland boy who'd drowned three years ago here in the bay, "—er, hi, um, nice to meet you—my name's Jack, what's yours?"

14. Necromancer AU

Mama had spellbooks on the bookshelf and a cauldron by the hearth, but it was a secret; she and Jack weren't supposed to know. Jack snuck a look once and got his ears boxed for his trouble - magic wasn't for children, Mama said, the witchcraft not made for them.

But the day after Jack fell through the lake… well, Mama's anger was a fair price to pay, Emma thought, if only she could have her brother back.

She drug the Grimore to the lakeshore and carefully began to read aloud, her lips forming each letter, her tongue chasing each foreign vowel, letting the spell spread its wings around her, slowly taking shape, until at last, the dark phoenix screeched and cried and flew from the air, crashing through the hole in the ice and diving deep into the lake.

Something stirred in the cold, dark waters, and, peering down, Emma gasped —

(magic wasn't for children, Mama said…)

—whatever was down there might've had Jack's face, but she knew at once; that was not her brother.

15. Office AU

Ever since Jack joined their team at the office, things had been trouble, but not the kind Aster had been expecting.

North, the bludger, caught Aster sighing at the sight of Jack in a tie—and immediately started scheduling the two of them on a 'group solo project' in hopes of getting them together.

He wasn't the only one playing Cupid—Tooth already 'accidentally' scheduled their lunch breaks together, Sandy'd gone and tried to set up a blind date twice, and even Pitch attempted, unsuccessfully, to lock them in a supply closet together to, quote, "just kiss and get this nonsense out of your systems, already."

"They think we're a new office romance," Aster informed Jack after work one day, torn between annoyance and amusement; "…should we tell them we've been dating for almost eight years?"

"Mmm, well, we could," his boyfriend made a show of thinking it over, but the trickster glint in his eyes told of another idea entirely, "but, let's be honest, wouldn't you prefer to have a little fun with it, first?"

16. Photographer AU

Maybe she was losing her touch.

Ana - "Tooth", to her friends - loved taking pictures in her spare time—whether snapping pictures at weddings and birthdays to preserve precious memories, or just taking photos of strangers on the street, she always had a keen eye for the perfect portrait… except when it came to Jack Frost.

He was a teen that walked by her apartment every day, and she didn't know what drew her to him (maybe his white hair and blue eyes, maybe his stunning smile?) but whenever she tried to actually snap a picture as he passed by her favorite park bench, it came out blurry, like he was some sort of cryptid, or worse, by the time she scrabbled for her Nikon and got into position, he'd disappear altogether.

Not this time, she told herself, spotting white hair round the sidewalk corner; snatching up her camera, fighting the butterflies in her chest, she approached the stranger and asked with a smile, "Excuse me, uh, weird request, but could I maybe take your picture?"

"You…" The teen's voice was low and awed, "…you can see me?" he asked, and before Tooth could process that odd question, a walking pedestrian passed through him like he was a ghost, and he vanished into thin air.

17. Quarantine AU

"But we're not sick," Jack insists as tendrils of dreamsand corral him inside the clean room with Bunnymund; "…at least let us have separate rooms, you can't make me quarantine with him, I'm telling you, this is ridiculous—"

"Oh, pipe down, Frostbite, you really think North has two clean rooms just lyin' around?" Bunnymund snaps, not happy with the situation but at least understanding the logic; Ms Bennett was sick, which meant Jamie and Sophie might be sick, which meant, as the two Guardians who visited most often, Bunny and Jack had to isolate as a precaution until they knew for sure.

But instead of accepting defeat, Jack whipped around to face Bunny, a glint in his eye, and said, "…you do realize that the incubation period for COVID-19 is like two weeks, right?"

Bunnymund paused a moment, letting the implications of that sink in: two weeks of quarantine… locked inside… with Jack?

"On second thought…" Bunny said, a moment too late, as the door locked soundly behind them.

18. Royalty

Not many knew that the Moon had an heir.

Sequestered away in the farthest reaches of the Kingdom, Jack Frost waited, living his immortal life in obscurity, a face in the crowd, waiting for the day his father would summon him back to his side. He waited, but no word ever came.

But then, an invasion from the usurper, Pitch Black, seized the throne and took the name the Nightmare King, ruling the realms with an iron fist.

To stop him, the Winter Prince must step up and claim his rightful place on the throne, but after years of neglect from his father—and spending time among the common folk—does he even want to go back?

19. Soulmates

When humans met their soulmates, they saw true color for the first time.

Most could see flashes before then, just impressions of hues that would someday become their favorite colors; reds of romantic sunsets, blues of their soulmates eyes—it was why, for Easter, Bunny always colored his eggs so vibrantly, to give the tots a glimpse of what, or rather who, was waiting for them in the future.

Jack Frost, Bunny knew, could see color, judging by the way he picked the perfect blend of blues to complement the pastel greens of his egg—and inwardly, Bunny cursed, because not only had he gone and fallen for a bloody showpony like Jack, he'd had to go and fall for one that was already spoken for.

"So, mate…" His unrequited crush was not Jack's fault, though, no need to reflect his bitterness; Bunnymund reluctantly picked up an egg to paint, sidling next to Jack, "…How long've you been able t' see color?"

"Oh, you know," Jack said casually, "—Since '68," and Bunnymund nearly dropped the fragile egg he was holding in surprise.

20. Tattoo Artist AU

"I want two," North said, motioning to his bare arms, "'Naughty' on the right, 'Nice' on the left, maybe surrounded with holly, or reindeer, or pine trees - make it Christmasy!"

"…You're joking, right?" Aster asked flatly.

He'd heard North make this request before, of course, but it was one thing to wax poetic about an idea over drinks at the local pub, and another thing entirely to hear it when North had his butt planted in the client chair at Aster's tattoo parlor, eyeing the inks and needles with interest.

"Of course I am not joking!" the Russian man burst out, a twinkle in his eye, "Tattoo is only fitting—I take my job as Mall Santa very seriously—so can you do this, or no?"

Well, Aster mused darkly, reluctantly grabbing a paper and starting to sketch ideas, bringing his friend's request to life; At least he's asking while sober, this time.

21. Undercover AU

They seemed like good people, if a little arrogant and self absorbed… Jack almost felt bad, lying to them.

Remember, he could almost hear Pitch's voice in his head, don't let your guard down… they may seem nice on the surface, but thanks to their methods, thousands of spirits have ceased to exist, and if we don't stop them now, we very well might be next.

It was almost too easy to infiltrate their group, throwing out token protests all while weaving his way into their good graces, except Bunnymund's; he'd be a tough nut to crack.

But when North finally 'talked him into' the sleigh, bound for the Tooth Palace, Jack knew he had them, hook, line, and sinker. He paused only long enough to shoot off a prewritten text to Pitch, so the boogeyman would know that everything was going according to plan:

'I'm in.'

22. Vampire AU

It was difficult to tell, at first glance, which one was human and which one was a vampire.

Pitch was the tall, dark, well dressed stranger with a sharp gaze and a dignified air; Jack was a scrappy hellion in a hoodie, who flashed smiles and cracked jokes and preferred to go everywhere barefoot.

Most didn't notice, until a second glance, which one had fangs, or the predatory glint in his eye, and by the time Jack got that close, it was all over.

"Perhaps if you acted more… distinguished," Pitch picked his words carefully, as he watched Jack sink his teeth into his latest meal, "Then perhaps more outsiders would try and treat you with fear and respect?"

"Oh, Pitch, stop taking yourself so seriously," Jack grinned, dabbing blood off his chin, "…that's one lesson you'll have to learn before I agree to turn you — Immortality will mean nothing in the grand scheme of things unless you learn to have a little fun."

23. Wings AU

Chocolate did funny things to a Pooka.

Sometimes, consuming it made Bunny grow six arms; sometimes, more muscle; sometimes, it was a third eye, and sometimes—

"Wings," Jack whispered, awed and breathless, the battlefield below forgotten, "Those are wings, you have—oh my god, this is the best, can we go flying together sometime?!"

"Ugh," Bunnymund swallowed, fighting down the vertigo that always came with heights as he perched on a building ledge and let his large, gray wings fan out behind him for balance, feeling absolutely miserable.

"Cheer up, Bunnymund, and look on the bright side," Tooth consoled, flittering up to pat his shoulder, "Once North finds out he's the only Guardian who can't fly now, he's gonna be so jealous."

24. X-Men AU

"Mutant," his mother had spat, like a dirty word, just before throwing him out on the streets with nothing to his name but the hoodie he wore on his back.

Jack Frost (he hadn't called himself 'Overland' in years, now) didn't regret his powers—if his X-Gene hadn't activated during that ice skating accident, his sister would've died—but he did wish, desperately, that the change hadn't come with a pallete swap, or at the very least, he wished he'd had time to dye his white hair before his parents came home.

'Could've been worse… at least I can still blend in, unlike some mutants…' Jack mused, sipping from a teacup as he listened to a lady with a bird mutation (feathers and all!) give her shpeil about some private school she wanted him to join.

"—and that's why we think you'd be a good fit for the Guardian's Institute for Gifted Youngsters," she finished, flashing a smile, "…so what do you say?"

"Mmm…" Jack mused—three years ago, freshly homeless, he would've jumped at the chance, because an environment where he was welcomed and accepted was everything he'd wished for—

"…how 'bout, 'no'?"

—but three years on the street taught him everything had a price, and Jack had yet to hear the catch, so if these Guardian wannabes wanted to have his trust, they were going to have to work for it.

25. Yeti Strike AU

Dear Mr. Claus, the letter read,

We regret to inform you that we find the conditions in the Workshop deplorable. Long hours, low pay, and no paid vacations are bad enough, even without the elves running around and blowing things up day after day.

We have written this letter to inform you that we have unionized, and until our demands are met, we are officially on strike.

"Strike?!" North demanded, appalled, "…but it's five days before Christmas!"

Hiding up in the rafters, Jack Frost ducked into the shadows and resolved not to tell North that he'd kiiinda seen this coming — encouraged Phil to do it, actually — because judging from Santa's tone, if he found out, Jack would be back on the naughty list for sure.

26. Zombie Apocalypse AU

Jack wasn't sure he trusted the Australian man, exactly, but it wasn't like he was spoiled for choice; the border was choked with zombies, and if Jack was gonna get to the research station, he needed some serious help.

"Look," Jack said, huddled by the campfire, "see?" as he rolled up his sleeve to reveal the marks, a crescent shape of teeth on his forearm, punctured down to the bone.

"Crikey!" Aster shot to his feet, alarmed, unsheathing the knife from his belt, "—you were bit, you're—!"

Jack stayed where he was, fighting an eye-roll, long enough for Aster to take a second look - to notice the wound was healed over, that there were no black veins or rotting sores, that the Fearling infection, oddly enough, hadn't taken root.

"—You're… immune," Aster whispered, and met Jack's gaze, flickering, at last, to life; "…and if you're tryin' t' get to the research labs, then that must mean—there's hope."