Author's Note

Patently, Sas Trihoof was made on a PONY GENERATOR! He is technically the product of "generalzoi" on Deviantart. So I can't really take any credit for the art. But I had the idea for a Side-Angle-Side congruence postulate pony for a long time—randomness at its finest.

Sas Trihoof

Good... God..." was all that Alondra could presently say. An impossible creature stood right outside the car; Mary herself, who had actually considered the possibility of Stacey's story holding a bit of truth to it, could still not believe the exaggerated proportions, freakishly large eyes, green hair, and glowing horn of the stallion—if one could truthfully call it a stallion—standing in the open door. It grinned stupidly.

"Who are you?" Stacey inquired quietly.

The grin grew wider. "I had been preparing to ask the same question! Who are you, and what,"—the newcomer tapped on the cool metal of the minivan with his front hoof—"is this thing?"

There was no answer; Alondra had fainted. Mary felt like her world had gone from bizarre to utterly surreal. Stacey eventually piped up.

"Thisiz our Toyota..." the six-year-old explained. "It takes us all sorts of places."

"Did it take you here?"

"Yeah! But I don't like this place. It's scary. My Daddy and my brother went away to find a gas station, but they're not back yet. And I'm super sure that Equestria doesn't havva gas station."

Mary, ever-so-slightly trembling, leaned forward and looked their inconceivable visitor square in his bright, carrot-colored eyes. "Really," she murmured. She wore a lost expression. "Who are you?"

"Trihoof," he stated, almost proudly. "Sas Trihoof."

"Sass Tryhuff?" Stacey repeated.

"Well... Yes. Sas, as in the S.A.S congruence postulate; it states that if two planes and an angle of one triangle correspond with the two planes and angle of another triangle, then those two figures are congruent. That's what S.A.S is: Side-Angle-Side. It's a clever mathematical law, really. Oh, Celestia... I just love triangles!"

Mary had never felt more adrift. "Okay...? Please, Sas—er, Mr. Trihoof—Can you explain to us where we are? Why isn't the sun rising?"

"Well, you're in Equestria. Your younger companion seemed to know that," Sas said, his brows high. "Oh, and please—no Mr., no Trihoof. Simply Sas will suffice. Oh, and"—his horn suddenly flashed bright orange, as did his eyes— "I think it would be best to conceal ourselves."

A fiery bubble exploded from the stallion's glistering horn. It surrounded them all, crackling with hot energy. "Don't touch surface of this field," he added. "It'll burn you, but that's a fair price; it hides us from the view unwanted visitors."

"An invisibility spell?" Mary asked, trying her best not to focus too much on Sas's glowing eyes.

"More so one for camouflage. And if anyone runs into it by accident, well... They're getting burned, too. Badly, in fact."

"That's horrible!"

"As aforementioned—fair price! I'm amazed you all haven't been gobbled up by timberwolves. You also inquired about this cursed, never-ending gloom; that can be attributed to the Moon's damned "everlasting night" tomfoolery. Come out your... your Toyota. I'll elaborate."

Trying to ignore their unconscious mother, whose reaction Sas found to be rather amusing, Mary and her youthful sister exited their minivan; when faced with the front of the vehicle, Mary registered the damage. The grille was cracked and messy. The hood of the car had been pushed back at a slight, unnatural angle. Everything else boasted several small dents and bits of scratched paint; the car reminded Mary of a cocksure teenager, flaunting his black eye after winning a fight. The sturdy Sienna had acquired such damage by squashing a pair of vicious timberwolves, after all.

"Alright," Sas said, seating himself on the dirt. He sat like a dog would, which perturbed Mary; standing up and lying down were the only two positions she had ever associated with horses.

Then again, regular horses don't grow small green beards or obsess over triangles, either, she thought to herself.

Sas's wide grin faded as he began to recall past events before Mary and Stacey, who now sat atop the hood of the minivan. "It happened quite some time ago," he began. "Nightmare Moon returned from her thousand-year banishment. After quite a bit of work, she managed to blast Celestia straight to the moon. I could've sworn there was an obscure prophecy around Equestria somewhere, speaking of six friends who could have stopped it all, but alas..."

Mary did not need to ask why Nightmare Moon was banished; Stacey had explained it all to the family last... night? The young girl had explained the whole affair of eternal night as well, but Mary had found herself in dire need of confirmation.

"Without Celestia to ensure the arrival of daytime, things got bad. Very, very bad. The sun never rose again, obviously; timberwolves started to spread and attack, panic and crime ravaged Equestria, the Moon killed and imprisoned innocent ponies with impunity... all that fun stuff. After Celestia's defeat, one of the first things the Moon did was go after all the great wizards, alchemists, and mathematicians—like myself—for we were the only ones who could truly challenge her. She threw most of us in dungeons and sought to exploit our talents, with the intention of growing even more powerful. Those of us that remain free—also like myself—must always be on guard. That was part of the reason why I set up this camouflage spell. It's actually quite a complicated bit of magic; in learning it, I had utilize several complex mathematical operations, the majority of which required a deep and sophisticated understanding of... Triangles! Triangles and their related functions! Can you believe it?" Sas stared at his two listeners with wide, expectant eyes, whose radiant orange glow never dimmed.

"I... I don't..." Mary stammered. "I... I can... Okay?"

"My humble apologies!" Sas exclaimed. "I digress. Though the Moon hunts for the rest of my compeers and I, I must confess that I don't consider the entire point of her rule, per se, to be a bad thing. Eternal night isn't so dreadful. It's what comes with said night—panic, crime, death. And, of course, the Moon's iron fist." The white stallion's perpetual grin finally faded, if but for a moment. "Equestria's population has become an oppressed people. And even while I feel that something is wrong, that time was never supposed to take this course... I know that this is actuality. This is reality. I can't do anything about it, much like I can't do anything about the fact that a pair of triangles having all congruent corresponding angles fails to prove that the two triangles are congruent themselves. They might be similar, but never congruent. One might be tall, but the other will be shorter. One might be wide, but the other will be thinner. One might rule the world, but the other will be banished for a thousand years."

The three creatures sat in silence for a while, until Mary made a connection. It was a weak one, one that she could barely wrap her head around, but it existed, and she thought it was worth mentioning.

"One triangle might be tall," she said slowly, "but the other, whose angles are the same, could also be taller. One triangle might be wide, but the other... could be wider. One might rule—"

"Child," Sas interrupted quietly. "Celestia may be stronger than her dark counterpart, but Princess Luna was aided by the Elements. There's nothing anyone can do."