Magic, in Equestria is a very water-like thing. It flows in rivers through the ground- "ley lines", as the unicorns named it when they grew aware enough. It streams, it gushes and eddies and occasionally pools, as Tom's stony progeny and an overabundance of Pinkies proved.
It took slightly less than three days for enough contaminants from the Crystal Heart to penetrate down into said lines, sifting into points where the lines rose closest to the surface. Thankfully, the rapid flow of energies prevented the lines themselves from being clogged in stone, but as bits of arcane energy found itself eddying and dribbling away from the streams, they worked a strange alchemy on whatever was around them...and in a places where enough lines met, the mystical flows slowed enough to allow for stone to form- first small pebbles, then increasingly larger as more and more of the magic-fed conglomerate extended itself upwards towards the sun, and deeper into the earth.
Appleloosa would be the first, small witness to the results as a spear of blue crystal shot up from a nearby mesa at the crack of dawn:
Compared to most of Equestria, the laconic earth pony population was remarkably undisturbed by the results. While the occasional shard that was easily found scattered nearby was "purty" and "kinda tingly when you pick one up", the effects proved utterly harmless. The general store put bits of the "Appleloosa Blue Sky Stone" on sale as souvenirs the same day, though anyone could just walk across the tracks and pick up as many little shards as they liked. Why, it almost seemed like they grew there!
Thankfully, almost no pony populations sit above a large eddy of magical energies coming together, especially one that had already shown an astonishing amount of magical crystallization, the likes of which unicorns and other ponies had happily mined for their treasures and then abandoned, leaving plenty of room for such a growth to occur...
Well, at least it'll take a bit of time to fill in all that empty space below Canterlot. Who knows when that'd happen?
---
In Canterlot, there are plenty of "quiet spots". Libraries, rooms coated with privacy spells for ministers and heads of state to meet, diplomatic stations, and all manner of nooks and crannies in which somepony just wanted a break from the bustle of the city around them- or possibly just nobody to notice them for a while.
The best of these happens to be Princess Luna's bedroom. Or rather, the "Consort's" bedroom BEHIND her bedroom, much like the one behind Princess Celestia's, both thoroughly sealed off from the rest of the palace, unless you happen to know the secret passages. And the second layer of said passages hidden inside the first. Oh, and the third one for good measure, which only numbers amidst the living two alicorns, one spirit of chaos (because Discord finding out would have been a matter of time anyway), and...
...six ponies who were currently trying to sleep together on a pile of slightly secondhand pillows in Luna's favorite quiet spot of all. And honestly, if they'd been nearly anywhere else, they'd have heard the ruckus, between the small army of pressponies that had clamored at the gate, the Guard quietly herding most of them into someplace Luna could discuss that yes, the responsible ponies were safely contained, then the Guard not-so-quietly containing a brief riot when some of the press started to interview the Empire's refugees, and a VERY not quiet Guard taking care of the two members of the Canterlot Chronicle who somehow managed to sneak close enough to Princess Celestia's window during said riot to shout a few questions through a megaphone at the snoozing Sun Princess, then managing to start ANOTHER riot when they were dragged away screaming about whether Celestia was protecting her "hidden weapons" from the public eye, and finally the VERY loud Princess Luna politely asking the milling horde to remain calm and return to their tents. Worst, the castle kitchen had run out of coffee and Celestia had ended up awake four hours before dawn- the first happening shortly after the second. It wasn't going to be a great morning for anyone...
...but those six ponies. They had peace and quiet. At least on the outside.
---
Twilight Sparkle's mind was normally a peaceful and quiet place, too- the very image of her beloved Ponyville library, even if the "books" were a bit different. That would have been before it ended up occupied by five other ponies and one rather large old ram, all of which thought nothing of being there as they dreamed of a slumber party, a pelting storm keeping them wanting nothing more than to stay dry and warm in the arboreal sanctuary. Somehow, the giant he-sheep just seemed to blend in.
"Ooh! He's so big and fluffy...do you have to count him more than once?", Fluttershy said and proceeded to run a fingered comb through the wool, smoothing away a few tangles.
"I am quite big enough that once is enough for most, or perhaps I could recite all of the prime numbers up to one million, two hundred and ninety-nine thousand, eight hundred twenty-seven. That usually puts most mortals to sleep.", the ram said contentedly as the comb worked it's way through his wool. "You have a gift for making creatures feel loved and cared for. It is good that they will protect you in turn, great and small."
The yellow pegasus paused in her wool-gathering. "Protect? Me? From what? Where?", as a crackle of thunder sent her diving under the nearest table, sending the card game on it flying in all directions. Most of the other ponies in the room proceeded to spend their time in an impromptu game of "52-Card Pickup", except for the incredibly formally clad (for a sleepover, anyway) purple alicorn that was giving her ovine guest the eye.
"You all happened to be sleeping in a rather adorable-looking pile, it wasn't as if I could leave them all "outside" while we chat. Besides, it is a pleasure to meet your companions.", the ram diplomatically bleated.
It could only be described as a mastery of dream-working that except for Twilight Sparkle, nobody else had noticed a Celestia-sized ram with sparking silver horns as anything odd in the Golden Oak Library. The scattered deck of cards seemed to breed, leaving half the room carpeted with four suits. Other than a few groans from Rainbow Dash, the five ponies cleaning up didn't seem to find 52,000-Card Pickup any more strange.
"Wouldn't you fit in better if you'd looked a bit more like us?", said Twilight, mildly peeved at the phantasmal desecration of her home.
"A fluffy pony-ball would hardly blend in well. And besides, it would be demeaning. Would you rather meet me as a winged, one-horned ewe? Besides, false forms are for those who would hide worse things. And I am a spirit of inspiration and revelation, not some green-eyed shadow stealing secrets in the dark."
A memory of crossing horns with Chrysalis briefly settled in the front of Twilight's mind before she pushed the disturbing image back. Honesty really WAS the best policy.
"And your mind has been quite in need of inspiration, youngest cousin. I have seen it is hard at work..."
Twilight's eyes involuntarily slid to a book table piled high. Celestial Influence On Modern Sorcery, A History Of Lunar Conjunctions, Crystalline Enchantment, Sombra's Syllabus Of Geological Warlockery...did he say cousin?
"...but the knowledge you seek is not to be found through any library or book. It requires a new book to be written, an author, a source. I have come to ask you this. Would you be the one? You are not merely "The Element of Magic", you are, in many ways the symbol that is the thing itself- and what has been left wild may be set to order through that authority, given enough power."
"Write....rewrite the very nature of magic itself? Are you telling me to become something more powerful than...Celestia? Or another Discord? Or that thing that stole our bodies through the Elements?", Twilight blurted out as a shudder of disgust ran through her body.
"Nay, never, no- three times I tell you this cannot be so!", the ram rumbled. Outside, a near-miss seared a long strip of bark and branch, sending it burning to the ground- only to be struck again in a double-CRACK of thunder that pressed against the windows like an angry beast. and vaporized the fallen branch in mid-air. The storm's driving rain reduced the outside view to the occasional bit of swirling mist and a curtain of rain. Behind the princess, four of the five sleepover guests turned as one to look at Rainbow Dash.
"Hey! I didn't schedule THAT kinda storm again, not after Rarity complained for a week about what it did to her mane...", the pegasus said, waving off the accusing stares. "This isn't MY fault...hey, do YOU know anything about this, sparky?", as she buzzed across the floor to hover in front of Twilight's unponylike companion. The creature looked somewhat embarrassed and taken aback by the attention.
"I...yes, that was my fault. It was quite inexcusable. I apologize for scaring you, losing my temper and causing the storm to drop so much lightning that close to your friends.", he said, a rather appropriately sheepish expression crossing the wool-covered face.
"Hey, I was NOT scared Mister...mister...hey, wait! Who ARE you, anyway?", Rainbow Dash said, poking an accusing hoof. "You some friend of Twilight's? Why are you here anyway? Why didn't she tell us you got invited for the sleepover? Have you been messing with MY weather team's clouds?" Jab, jab, jab...
"Twilight calls me Ram....uh? Yes, Ramuh. It is a good name. I, too dwell high in the skies, in the mountains where the wild weather rolls down into the Everfree. Once, you ponies called it the "Cloister of Storms". She and I have corresponded before on matters of history and magic, but I happened to be in the area and wished to meet more closely. She has been a most gracious host, even though I have disturbed your "sleepover". May we perhaps discuss it further over a game of cards, once you're ready to play again?.
The suspicious light in Dash's eyes faded as Ramuh's formal tone and speech filed him firmly under the category of "another one of Twilight's egghead friends", and with a final pugnacious sniff, she turned...
...and turned back for one more jab. "Don't you ever do that lightning stuff around Ponyville again, or I am SO gonna take you on, Twilight's friend or not!"...then dropped back to the ground to pick up a stray six of spades. "Stoofid cards" managed to get around the clamped teeth as she walked back to the rapidly growing table pile and deposited it on the top.
The glittering look in Pinkie Pie's eyes at the thought of "new friend" crossing with "party" warned Twilight that any further conversations would be very short indeed.
"Are you conversant with the construction of grimories, Twilight Sparkle? It was once said that given enough power, you could write the world into a book, but that you reached deep enough to find the right wordOOF"
"Hi! I'm Pinkie Pie! One K, two P's, and three eyes!"
The library vanished as if stomped by a hoof...
...and Twilight found herself with Pinkie's bandaged one giving her a smarting muzzle as she woke in a suddenly chaotic cuddle pile. The still sleeping Pinkie thrashed about, murmuring something about molasses and dandelion pies as she shoved ponies off the pillows in every direction. Finally, a too-solid jolt to Applejack's backside woke both of them up.
"MAH DOCK!", she squealed and proceeded to buck right back, sending Pinkie flying into an old four-poster bed with a clatter of musty linens and collapsing canopies. The noise managed to wake anypony who hadn't already been struck in a tender location. "That mean ol' ram, I TOLD HIM NO MORE-.what?", a confused Rainbow Dash got out as she narrowly avoided decking Fluttershy, who vanished save for a shivering pink tail waving like a surrender flag from under a blanket. "Aww....I was having an awesome dream about having a party for the Sleepy Sheep!", Pinkie's voice wafted from the wreckage.
A second BOOM even louder than Pinkie's collision silenced the squabble- Twilight shoving the trap door leading out open with a single triumphant jerk of her horn. It lay cracked in two, nearly torn from it's hinges by sheer enthusiasm.
"I've GOT IT!", the princess exclaimed.
"Got a burr under your tail?" "Got a horrible case of morning mane, darling?" "Got breakfast?" "Got *yawn* five more minutes?" "Is....is it going to get ME? *squeak* "
"No no no! How to fix all the broken magic! I've got to write a grimoire, the most importantly magical book of magic that ever got spelled! All I need is...is...oh my gosh, I need..."
"YES?" came from the five ponies tangled in the mostly-dismantled bedding.
Twilight told them, and in less than a minute (give or take a moment) the tunnels echoed with the sounds of running pony-feet.