"I'm a what?" Rarity was completely shocked by this sudden revelation. She'd never heard such a ridiculous sounding thing in all her life. And she'd heard some fairly ridiculous things.
"You're a unicorn," the stallion said. "A rare breed of pony that can do all sorts of fancy, powerful magic. We try to keep them from the earth ponies, though. They get jealous, bein' useless and all."
"That's segregation!"
"If you were the only earth pony in a group of unicorns, and had to stand by while they all did their fancy magic lifting things, with you unable to do anything but watch while they excluded you, what would you do?"
"I'd call them out on being impolite. I'd tell them to cut it the- oooooh..."
"Right then."
"What's your name, anyway? How do you know mine? I've never even seen you before."
"Mac," he said. "Don't worry about knowing who I am, but I've been watching you for many years. Making sure you were safe until you were ready."
"That doesn't exactly make me any more comfortable around you," she said. "Can you do magic? Is that why you're here?"
"Used to," he said. "Then there was this whole debacle with being confused as a princess and they charged me with impersonating a royal official and the Council took my horn." His voice was sad, tinted with melancholic nostalgia. "But that's a story for another day. Come on, we have much to do, and very little time to do it. Once you've entered the magical realm, He'll be looking for you."
"Who's that?" Rarity wasn't sure she liked this at all.
"I'll tell you later, right now we have to hurry. Grab your things."
"I don't have any possessions!" Rarity insisted.
"Well then, what are you waiting for?" Mac gave her a nudge, and encouraged her out the door. He walked at a brisk pace, and being such a large pony Rarity found herself having trouble keeping up. She wasn't sure why she followed him, although she felt oddly safe in his company.
"Are you sure we're going to the right place?" She asked. "There's nothing down here but an abandoned housing district. It's decrepit and falling apart, not to mention unsafe living conditions. There's no reason for us to be down here."
"Or is there?" He asked. He stopped in front of a decaying wall after leading her down a series of frighteningly back road alleys. Nopony came down here much anymore. "This place is filthy... the hairs on my neck are standing up. I feel like in another reality my alternative self wouldn't be caught dead here. Can't say I blame her?"
"What if your alternative reality self is a boy?"
"Well then I'd hope he'd have much more sense about following strangers into dark abandoned alleys..." She said. "If I had a mind to I could have you arrested, you know."
Mac nudged at the wall with his nose, seemingly ignoring her threats. Despite her worry about the way this was all playing out, Rarity very much wanted to see what it was all leading to.
"This way," he said, and walked straight into the wall, vanishing with scarcely a ripple.
Rarity blinked several times, standing there in shock. "I really don't know about this..." she said. "Maybe I should just try my luck on my own, after all, I'm sure I could get a job someWHEEEEEERE!"
Mac's hoof had reached back through the wall, and taken hold of her front leg. Unceremoniously, she was pulled through the wall.
Immediately, Rarity found herself standing on what appeared very much to be a blackened, dead field. Looking behind her, she saw no wall, no city, only an expanse of torched grass and dead trees. There was not a single birdsong to be heard, not a single chirp from a single cricket.
"This place is... death..." She whispered, her previous worries overridden by such a vast display of destruction.
"Who could have done this? What could have done this?"
"He did," Mac said. "In his never ending search for the Chosen one. That's you."
"Me? But I've never done a single amazing thing in my life!"
"Not yet you haven't. But you have the potential for it. And that's what he wants to destroy. We have to move quickly, as long as we keep low we should be alright. Let's just get to the castle first."
Rarity was shaking her head. "Slow down, slow down, I don't know any of this! What castle?"
Mac raised his head and pointed a large hoof towards the far distance, where a faint shimmer on the horizon could faintly be seen. "Celestia's School for Magic Unicorns. That's where you're going to train."
"And it's safe?" He can't get in? Wouldn't a giant castle be the first place some evil overlord would target?"
"No. Far too many spells protect the place. But what you see around you..." He swept a hoof over the desolation. "This is a reminder of his last attempt to break the barriers. The wards held, but the valley did not."
"And where are we?" Rarity asked. "Who is this horrible thing that wants to kill me?"
Mac frowned, and looked out towards the castle.
"We do not speak His name, for even the sound of it strikes fear into the hearts of the brave. What you see around you used to be a thriving forest community called Flutter Valley. And the one who pursues you..."
"Yes?" Rarity asked impatiently.
Mac looked her in the eyes, his own filled with fear, regret, and determination.
"His name is Lord Smooze."