Celestia’s Royal Academy for Gifted Unicorns was THE premier school for the study of the arcane arts. Only the best and brightest got accepted into its halls and failure to pass the stringent exams needed to remain in attendance was a fate only avoided by the colts or fillies of influential nobility with any certainty. This immunity did not extend to the struggling grad student named Starswirl. This was, in all honesty, a bit of a problem considering he only had a week to come up with both a new spell system as well as a proof of concept for it. Neither of which he had any idea where to start on.
So there he was sitting at his desk at 3 in the morning staring blankly at the equally blank paper in front of him. The crumpled remains of its fallen brothers and sisters sat in a pile near the waste basket. He was stuck, kept getting distracted by such mundane questions as wondering what would be served for lunch that day or if he should try to grow out a beard. To make matters worse the ominous red glow of the room was starting to give him a headache on top of that. Wait… something about that last thought wasn’t quite right. Starswirl glanced up at the Enchanted crystal in his desk lamp. Eeeyep… still blue-white. He spun round to face the source of the red light only to find a glowing red rip in the fabric of reality floating in front of his bedroom door.
“Oh dear…” Starswirl said eyeing the rift wearily, that was NEVER a good sign. In fact, in his experience, glowing portals of any kind should generally be avoided if you weren't fond of having extra limbs or particularly liked your sanity where it was. He therefore generally made a point of avoiding them. This one however, had apparently come looking for him… and given its position leaving the room and hoping it would get bored and bugger off was out of the question. So faced with this harsh reality the young mage did what he considered the only sensible option left available to him and scowled at it disapprovingly hoping it would get the hint and go away.
Being that a portal is far more akin to a window or hole in the ground then any sort of rational thinking being this portal did nothing of the sort. What it DID do however was flash brilliantly, and with a particularly unpleasant noise the defied description, violently eject an unshaven stallion onto Starswirl’s bedroom floor that looked as though he needed a bath and a few days of bed rest. Starswirl edged around his now toppled stool. As he moved past it the soft glow of his magic fastened around the yardstick he kept next to the desk in the event of just such a magical emergency and with great care and unerring precision began to prod the intruder with it repeatedly. The unicorn on the floor moaned piteously and rolled over. It was another Starswirl. Starswirl number one let the yardstick fall to the floor in suprise and shuffled back away from himself. Starswirl number two sat up and smiled reassuringly as a slightly insane looking copy of yourself you suspect may be an evil paradox twin can.
“Do not be alarmed. I’m you from exactly one week, 7 hours and 12 minutes in the future.” The Current Starswirl couldn't help but feel this WAS something to be alarmed about. Because apparently sometime in the next week he was going to go insane, stop bathing and start opening up portals in space time all willy nilly with no regards to what it might do to ether the fabric of reality or his sanity… though that last bit was obviously a lost cause if he was already having future selves popping about. The mad pony even had bells tied to his hat! Bells! But wait… if his apparent soon to be acceptance of time travel was due to insanity… and his insanity was due to future hims showing up to cause it then what would happen if he—
“The universe explodes,” said future Starswirl casually as he stood up with a quiet jingle and dusted himself off “or implodes… one of those things.” He made a vague waving motion with one hoof.
Present Starswirl wasn’t put off with the himself for knowing what he was thinking he WAS himself after all, so obviously he’d be able to figure it out… also he was a bit distracted by the content of the warning itself. Exploding universes?
“Does it really?” he asked. “Why?”
“Don ‘no” future Starswirl shrugged. “It’s what future me said to me when I was still past me… if that makes sense.” Current Starswirl thought about this for a moment and nodded sagely.
“Not in the slightest.”
“Don’t worry it will” said future Starswirl smiling in a knowing way. Current Starswirl stared at future Starswirl. Future Starswirl just kept smiling. Eventually the clean shaven Starswirl became unnerved by this and coughed into his hoof expectantly.
“Was there, um, a reason? You know for coming back and visiting?”
Future Starswirl slapped a hoof to his face and levitated a thick stack of papers out from what was left of his robes. “Nearly forgot” he said. “Here’s your, my, our completed thesis and proof of concept. Everything you need to know about the spells involved in time travel and how to do it without erasing yourself from time. You’ll have to read it over and start working on the equations necessary if you want to be able to come back to give it to yourself in time to not stop existing from a grandfather paradox. I've never tried not existing but I’d imagine it’s not fun.” The papers where unceremoniously shoved into Starswirl's hooves “remember you only have one week. Not sure why. Maybe whichever version of us that decided it would save trouble to use our research to just come back and had it off to himself in the past didn't think the timing involved through. Now I know you have a lot of questions but I don’t have time to answer them the spell only lasts so long you see and I need to get back to reformatting it so that it doesn't use portals for egress. Nasty business portals.”
Before current Starswirl could even properly process the verbal wall of exposition that had just assaulted him enough to question it future Starswirl disappeared abruptly in a flash of red light. Current Starswirl, now the Only Starswirl to be in existence as far as he knew, looked from where he would be having been standing (and he could practically FEEL his sanity fleeing in terror just thinking that sentence,) to the papers in his arms. He had been right all along. They had called him paranoid but he was definitely right about the inherent evil that came from having anything to do with portals. Carefully he set the notes on time travel down on his desk and returned his faithful stool to its upright position. He may have lost his sanity preemptively but there was work to be done… and at least two good things had come of it. He wasn't likely to be expelled from the academy now that he had completed his thesis on time and more importantly...
He now knew with absolute certainty that he looked absolutely dashing with a full beard.