Twilight simply gaped at the familiar, utterly impossible figure in front of her. The red, yellow, and blue lightning-bolt cutie mark. The same grin. The little nick in her left ear. She heard a fluttering moan and a loud thump. That sounded like Rarity, a corner of her mind noted, And for once, it's not an over-reaction.

Applejack was the one who broke the spell. “I don't know who you are, but we're expecting the attendant,” she said hoarsely, “We got a funeral to go to.”

“Uh... It's me, A-J. You know, Rainbow Dash? You've been bucking too many trees,” said the Pegasus, looking confused.

Applejack bristled. “Oh, no you're not! I don't know who you think you are, but this ain't funny. This is just plain cruel, and you've got five seconds to explain or get the hay out of here before I start cracking heads!” she spat, her voice rising with anger.

Twilight blinked, slowly surfacing. It was her, it had to be her. There was no other possible explanation. She knew that mare almost as well as she knew herself. “Rainbow?” she whispered.

The Pegasus grinned. “Hey, Twilight! You know, black really isn't your colour!”

“This ain't funny! What they hay is wrong with you, that you'd do this?!” screamed Applejack, losing her fragile composure completely. She went to throw herself at the imposter but was swept up in a ball of yellow light, thrashing madly.

“Oh dear. I think I'd better explain,” said a voice. One of the black-clad figures stepped forward, cutting between the enraged farm pony and the Pegasus – Rainbow Dash?

“Who are you?” asked Pinkie in a stunned voice.

The pony, a pale-yellow Unicorn, grinned at her. “That is not important, but for the moment you may call me Jay. My taciturn friend over there is Kay.”

“Jay? What sort of name is Jay?” asked Twilight stupidly. Her mind was still refusing to function past one overwhelming certainty. Rainbow Dash.

“It's short for Jehoshaphat,” mumbled Pinkie absently.

The pony that called herself Jay blinked, “How in Equestria do you work that out?” she demanded.

The other black-clad pony, a green Pegasus, snorted and adjusted her tie, “Nice going, Jay!”

“I hate my mother! Why did she have to give me such a stupid name!” moaned Jay.

By this point, Applejack looked like she was about to self-combust, and Kay took over. “Well, leaving aside your mother's social inadequacies-”

“Hey!”

“-Inadequacies,” Kay repeated with relish, “I think these ponies want to know what's going on. Well, ladies, I'm happy to say that this really is Rainbow Dash. A happy reunion, and all that.”

“Rainbow Dash is dead!” Applejack barked harshly. “I saw her body, held her hoof one last time, and it was cold!” Her voice broke on the last word. Fluttershy looked like joining Rarity in unconsciousness, while the hints of a crazy smile danced on the edges of Pinkie's mouth.

“There was a misunderstanding?” said Jay hopefully.

Twilight's mind kicked into gear. “No there wasn't. There was no misunderstanding,” she growled angrily. Her magic shot out, seizing the two ponies in black around their necks and hoisting them helplessly up onto their hind legs. How? How, how, how, how...

“A clone,” said Twilight eventually, nodding slowly to herself. “It's the only way. The pony we knew as Rainbow Dash is dead.”

“Gah! They said she was smart,” choked Jay, her rear hooves scrabbling for purchase.

“Let us down. We'll explain,” wheezed Kay, slowly turning red.

“Keep going,” said Rarity's voice feebly, as she started to come around, “They deserve it.”

“Let Applejack go first. Then explain, and it had better be good.”

The yellow light around Applejack disappeared with a pop, and the farm pony dropped back onto her hooves and rounded on her erstwhile captors, absolutely incensed. Slowly, Twilight lowered the two Unicorns back down.

Jay rubbed anxiously at her throat, while Kay adjusted her tie again with some aplomb. “A long time ago-” she began, but Rarity cut her off,

“This isn't the time for an ancient history lesson! Tell us what happened to our friend!” she hissed angrily.

“Do you want to hear this or not?” demanded Kay, before continuing, “A long time ago, during the first Discord War, Princess Celestia had the service of a Pegasus pony called Rainbow Dash. She was the commander of the Airborne forces in many a battle and became one of the Princess' closest friends as they fought side-by-side for many years. Finally, the Princesses managed to locate the Elements of Harmony and risked an expedition to recover them. They were successful, but while they were away, Commander Dash was killed in a small, rather pointless skirmish near the Neighagara Falls. The Princesses managed to defeat Discord, but Celestia was devastated. She threw herself into rebuilding Equestria, and it was many years before she truly smiled again. Everypony needed a Rainbow Dash in their lives, she used to say. Well, the Pegasus Council was listening. And after many years, they made it a reality.”

“They always told me I was named after a hero,” said the new Rainbow Dash proudly.

“It's a little more complicated than that,” said Kay. “A small portion of Commander Dash was frozen at a facility in Cloudsdale and studied for centuries by a team of crack Pegasus scientists. Eventually, they found a way to re-create the Commander using a special technomagical machine. They called it... the Pegasus Device.”

“But we've all been to Cloudsdale? Where did they hide this thing?” asked Twilight, her head spinning.

Jay laughed shakily, “Why, in plain sight, of course! Who would suspect something like that in the weather factory? Plus, I think somepony got a kick out of calling it the Rainbow Factory!”

“Rainbow... Factory?” asked Rarity weakly, “You mean...?”

“Well, not quite,” admitted Kay. “We only produce an exact clone of the Commander once every couple of generations, but there's a few other ponies out there with her shining qualities, scattered across Equestria. Plus we need to keep a few spares, as they seem to find ways to do themselves in on a regular basis. This one's worse than most, though; this is the fourth Dash unit we've had to replace in the last two years!”

“Replace?” Twilight gibbered, appalled, “But the Elements!? How would that work?”

Kay shrugged, “This Dash unit turning out to be the Element of Loyalty was a bit of a surprise. We were rather worried the first time we had to replace her after this was discovered, but it doesn't seem to matter – which is a bit of a bonus!”

“Yeah, tell me about it,” said Rainbow Dash, rolling her eyes.

“We just have to clone her off a few times, then inject the appropriate memories and she's set to go.” added Jay, before rolling her eyes at their horrified expressions. “How do you think she affords that fancy floating palace of hers? We've got to have a base station to monitor her off, and this way we get a full upload every night.”

“How... how does she know this? Why doesn't she tell anypony?” asked Rarity faintly, as Spike fanned her with his jacket.

Jay grinned nastily, “She's programmed not to, of course!”

“P-p-p-programmed?” Fluttershy squeaked in horror.

“We've added a few refinements over the years. This Dash unit is a real pain, actually. I mean, you're a smart Unicorn, Twilight Sparkle, think about the Sonic Rainboom for a minute! The forces involved... the air friction alone tends to vaporise them, which is where the Rainbow part comes from,” said Kay.

“So every time they do a Sonic Rainboom-” Twilight gasped,

“Yup! New Dash unit.”

“So why, how did you let her do it in the first place?”

Kay scowled, “Those smart-alecs in the lab got really drunk one night and took the restrictors off a filly Dash unit, then supercharged the hay out of it. Wanted to see how fast they could make it go, they said! The next time the darn thing tried to race, boom! Straight through the sound barrier, and bits of grilled filly all over the place!”

Twilight shook her head, trying to wrap her intellect around the information. “How?” she asked eventually, “How could the Princess do this to us?”

“Princess?” Jay looked blank.

“Princess Celestia! How could she toy with ponies like this! How could she-”

“What makes you think the Princess knows about any of this?” asked Kay, also looking puzzled.

“She must have noticed!” Twilight shouted, waving a hoof furiously, “How could she miss the reincarnation of one of her dearest friends?! You've even given her the same name!”

Kay shrugged, “I don't think she's noticed, or if she has, she only thinks that she sees the Commander's best traits in others.”

“Well, you're too late now,” said Twilight triumphantly, “There's so many ponies gathered out there, you'll never be able to keep Rainbow's return quiet.”

“Our colleagues are out there now, explaining,” said Kay, with a shrug, “I admit we were a bit slow off the mark this time, but it's happened before.”

“It must be time the Scootabot got another upgrade,” agreed Jay.

“Scootabot!” Rarity gasped, “But, but...”

Kay gave her partner a sharp smack around the back of the head, “Nice going, Bonehead!”

“Aw, come on, they must have noticed!” Jay whined, rubbing her ear, “You did, didn't you?”

“But that's my little sister's best friend!” shrieked Rarity and Applejack in unison.

“That'd be a 'no', then,” Kay sighed, “How did I get lumbered with you again, Jay?”

“No more,” said Twilight shakily, “No more, you can't possibly expect us to keep this quiet.”

“Not even to have your best friend back again?” asked Kay smoothly.

Twilight threw a stricken look at the revived Rainbow Dash. Was it really that simple? Could they just pretend that nothing had ever happened, and let things go back to how they were? Rainbow Dash's hopeful smile cut her heart to ribbons in her chest. It was so achingly tempting, but she knew it was seldom that easy in the real world.

Kay smiled kindly, “Look, we have a little presentation here which will explain everything. If you'd all just like to gather around. You, too, Rainbow Dash. And you, little guy.”

“I'm not a little guy,” Spike grumbled, stalking across to join them.

“Now, if you'd just like to watch here for a second,” said Kay, pulling a slender metal rod out of her pocket.

The world vanished in a blinding flash of white light.