"Don't you hate it when a simple research project sends you hurtling through the vast reaches of inter-temporal space? And it wasn't that big of a mistake, either - I just moved a little to the side and got it wrong by a single unit."
And to make things worse; the spell worked more or less as intended, just with a side-effect.
What? Not all miscasts had wacky and unpredictable consequences beyond the scope of rational thought, or even prevented a spell from doing what it was meant to do. Just because somepony tripped a little that didn't mean that the pony would fall.
*****
"Oof!" Twilight felt the wind get knocked out of her, her vision still a blur of stars and fireworks, her ears getting nothing more than a high-pitched whine trying to make a tune and failing miserably, while her nose sent nonsensical smells and her skin felt like it was being assaulted by slimy barbs.
She recovered... in under a second... not normal.
Seeing as how she was inside the library's lobby, somehow missing the carved shelves, instead of the basement, she knew that something was odd. That had taken more energy than simply teleporting to ground level, while also not feeling like any teleport she had ever experienced - it was too wavy. Teleports usually felt electrical, or warm, pulling and/or pushing... err... alright, maybe she wasn't fully recovered.
"Ah, Twilight! I didn't expect you to drop by so suddenly!" A stallion's voice came from somewhere upstairs; he sounded like a senior. "I'll see you in a minute! The girls aren't in, however."
"W-who are you?!" She said as she shakily got to her hooves. "What are you doing in my house?!"
"What am I- oh dear... you aren't my Twilight!" The stallion said. "Or any Twilight I've met before... I'll have to take measures."
"What?" Twilight steadied herself, and warily observed the door to the upper level.
An old unicorn stallion came out of it... other than a long, impressive beard and mustache combo that shamed all other owners of facial hair, she could not tell much about the stallion. His coat was yellow one moment, then blue the next, or even her very own lavender, with his eyes changing colors just as fast, although his mane remained the same gray as his beard; she recognized the effect as a kaleidoscopic disguise spell.
"Now, dear, I'll get in contact with somepony who can get you the help you need, and all will be fine, you hear?" He spoke in just the same tone her grandfather used to calm her down when she was just a filly... "Now, tell me, what were you doing before you ended up here?"
*****
"So... who was that? And why the library?" Rarity asked. Twilight had already told them that she had accidentally blown herself up with a miscalculated time-whatzit spell, thus ending up there. Well, that wasn't what she said, but that was what it amounted to.
"Ah, both are related; the key resonator element of the spell I cast was a perfect match..." Five minutes later. "... accidentally interacting with a protection spell against intruders that allows only certain ponies through, and, in fact, pulls them in; one of the ponies in the list being 'Twilight Sparkle'."
*****
"... with the self-identity 'Twilight Sparkle', plus a few other parameters, designed that way to skip having to traverse the surrounding area." The surprisingly spry old stallion concluded. They were taking tea around the central table, which was covered with many, many scrolls and the occasional equation that had been written directly on it before either pony realized that the parchment had ran out of space.
Twilight understood. The spell she used shared a similarity to a spell that was actually designed to transport a pony 'here', where 'here' was a point outside of her 'local' space-time. Her spell had also taken her off the constrains of the fabric of space-time by actually managing to punch a hole in it 'larger' than herself... which was a problem, but one that could be solved with help from the right pony.
"Wait, if the keys on the scroll are a match..." Twilight whispered as the epiphany hit her over the head; first, right now, she was in a place where time was too loose to affect things. Second: "That would mean that you either paid homage to another wizard... or... or..."
"Or all of my spells use the same components because I liked them when I made them the first time." He completed. The keys were simply the part of the spell that held it together (for those spells that needed such things) until it was actually cast, similar to bobby pins and needles, and usually were 'arranged' in different ways by each caster; it also had the benefit of making sequential casting of spells with similar keys easier; the author used them as a signature, while the ponies attempting another's spell used them as a reference, sometimes changing the keys for their own style only after being able to reliably cast the spell.
"You... you are Starswirl the Bearded. The Starswirl the Bearded!" She squealed and stared, wide-eyed, at one of her idols.
He chuckled and shook his head.
"Oh no, I'm just a Star Swirl, and my name is two words instead of one. You accept having other Twilight Sparkles running about, but not other mes?"
Twilight shrank back a little, blushing and rubbing a hoof on the other.
"Well, I already had a little experience with a one-use time-travel spell..."
"The spell that makes you learn it?" He gasped in shock, then grumbled. "Why, oh why... did anything good come out of it?"
"Umm... we made many renovations to... as many things possible, to make them safer." Twilight, while knowing that this stallion might not even have the same personality as the one she studied, was still stunned by having a wizard bemoan his work like that. "What happened in yours?"
"See, I appeared in front of myself and showed me my work, then I did everything to recreate it, went back in time, and showed it to myself... what a waste of a perfectly good week." He planted his face upon the table. "And I never did find out if what I said about the limit was true, or just playing into what I heard the first time."
*****
"It was decided that we should do something about my accident, you know, fix the hole so that... actually, he just said that the consequences would not be something I would like to know about." She had to agree; she had been studying time magic for a couple of loops, and quickly discovered that the potential for disasters was such that she trembled in fright.
Magic, the magic almost anyone - pony or not - knew, worked within the universe, but hardly affected the universe itself... her accident was precisely that - an accident. 'Common' magic interacted with... other magic, magic that she didn't know existed - until then. It was a little daunting, but once she had scratched the surface, she knew she would never turn back. The older wizard knew some, but they would need a little help, both out there, and back inside.
She had to hold a few details, for now, at least. For example, how she had squealed like a fangirl when he gave her permission to touch the beard - she couldn't help it! It reached almost to the floor, yet was always silky-smooth and lustrous!
*****
"I got here because of a similar (though less disruptive) spell, though it was a mistake, since I was working on an entirely different spell at the time." Star Swirl said, looking outside a window; it was like Discord was set loose out there. "I... found that I liked it here, and re-created my favorite workshop."
"This?!" Twilight gasped, wide-eyed. She understood, intellectually, that her own home might have not even existed by his time in her world, but the mere thought of such an important wizard favoring the place she called home still made her heart race with the kind of excitement only a passionate academic can have.
"Well, yes!" He chuckled. "That earthy scent, the feel of the live ley lines flowing all around you... it makes anypony feel more in touch with nature, don't you think?"
Twilight nodded. So inviting it was, it had taken no more than a day for the place to feel like a proper home. She always tought that casting spells inside felt warmer than outside, but, until now, she had believed it to be simply a trick of the mind...
"Ahh... well, this might not be the Astral Realm, but I'm happy nonetheless."
"Astral what now?"
"Oh, towards the end of my time, I was trying to make a new spell, to reach a place of magic that supposedly only the princesses could get to, but..." The aged stallion trailed off, lowering his gaze, ears flat against his head. "But I'm old, Twilight, old."
She was quickly at his side, patting him on the back. "But what does that have to do with anything? We found my mistake very fast, and you already have something to send me back! If it weren't for the beard and some wrinkles, I'd say you are at your peak!"
He shook his head and smiled ruefully at her. "Anything in here is unaffected by time; I am as fit as I was when I was young, but only here. This..." He tapped his head. "This went away a long while ago. And, while my legs look thick and strong, that is only because I managed to bulk up again, but my bones would protest my weight as soon as I leave."
Twilight let our a tiny gasp, covering her mouth with a hoof as she slowly realized what he was talking about.
"The head lauded as belonging to the most valued wizard of my time might as well be a coconut; thick, hard, and filled with nothing but sloshing liquid. If I leave, I'll just be a senile old fool that can't understand how unpleasant I am to be around." He sighed, devoid of the youthful energy he had displayed during their study session. "I think that's the main reason why my last piece never worked right... my age took away my ability to understand things."
She hesitated for a second, then bit her lip, but in the end, she gave the tired old stallion a hug.
"And I'm not the only one whose reason faded with age." He continued, though leaning a bit in direction of Twilight. "I heard that another one of me made an awful object called the All-icorn Amulet."
Twilight shivered, letting him know that she knew of it. She knew. Everything; from what the thing was, to the path language had taken to make an archaic saying into All-icorn, then further shorten it to Alicorn, much to the annoyance of the princesses...
She knew.
"One... one of the things my world's Starswirl was known for was defeating a unicorn that was crazed by that thing, and saving him."
"Hmm... at least something good comes out of it."
Twilight recalled Trixie's... return. She'd write her a letter, for a small get-together, after everything was fixed.
"What... what of an age spell?" Twilight asked, having had a burst of inspiration from the memory.
"Ah, not here, many spells affecting one's time don't work correctly here; I would need somepony else to do it, outside, after somehow making my senile self to agree. Yet, even then I would stay here; because of the girls... you should meet them some time, but this place soothes minds, and the troubles that plague one of them are lesser here." He said, sadly yet still resolutely, turning to a framed picture.
She promised she'd visit.
*****
"It was decided, then, that to fix things, I would need help - not just with the magic involved, but to keep me mentally sound by doing different things no matter how many repeats I am involved with." Twilight left out the personal parts, the technical stuff, and the parts that would just be plain confusing without the context. "And the starting point is just as important."
"Obviously, you can't just point and say 'oh, I would like to go there' just like that; no, for it to be quick there had to be some signal... a beacon, of sorts." She added with uncertainty, and blushed. "It just so happens that the... explosion from this morning was an excellent marker; not too close to The Event to make a maddeningly short loop, nor far away enough to make for an awkward wait. True, more time would help with the events in the timeline, but... well, it's not as good an idea as one may think."
"What kind of help can you get on... this side?" Rarity asked; Twilight had kind of made a point to tell them how strange all of it had been. "If the same events have the same outcome, who else but you could change that?"
"Why, you are sitting next to her, of course!" Twilight cheerfully replied. "She's not the only one, but you don't know the others yet."
Everypony turned to the earth mare sitting next to Rarity, while Pinkie herself gaped in surprise.
"Me? But why?" She tilted her head, pondering... something, maybe the secrets of the Universe, or just a new cupcake recipe.
"Your little celebration back in Canterlot, that's why." Twilight said, pointing. "You preempted Spike and Applejack making questions as they do when I come out smiling; things change around you, like the normal rules of reality don't apply to you."
"Can't you tell us something we don't already know?" Rainbow Dash deadpanned, managing to hold her flat look for all of three seconds before giggles and chuckles spread through the group.
"There's an oracle living in Canterlot; fate and destiny are her tools of the trade." Twilight said with an overly-happy smile. "The prices on some of the things she sells are insane, yet, for their function, are a steal. She also has been teaching me some unreal magic, and from that I've been piecing together the foundations to the magic she used to make what are, essentially, spirits (though 'summonable golem made of magic' would be more accurate, if a tad insulting)... Oh! And whenever I give it some thought, she might just be the scariest mare I've ever known despite being so friendly - unless what she told me about her best friend is true."
The others stared at her.
"What? You didn't know that."