Like Teacher Like Student
"I was hoping you would send her to my dimension," Discord said to Twilight wistfully, "Then we could be roomies. Way to not pick up what I was throwing down."
Twilight was annoyed but did not respond to his statement, nor did anyone else at the time. After it was over and ponies had started to leave, Fluttershy approached Discord to talk privately.
"Discord? Are you alright?" she asked.
"What? Oh, don't be silly, of course I am," Discord said. To illustrate his point, he produced a pair of googly-eyed glasses on fluttershy with a snap.
Fluttershy carefully removed the glasses. "Discord..." she said meaningfully.
"Oh, very well," Discord said reluctantly, "It's just... it does get rather lonely in the Chaos Dimension... once in awhile. A roommate might liven things up a bit."
Nearby, Celestia overheard the conversation. Her face lit up as she got a marvelously mischevous idea. Making her way to Twilight, she tapped her on the shoulder.
"Celestia? Is something wrong?" Twilight asked.
"Not at all, Twilight," Celestia said sweetly, "I was just hoping you might indulge my curiosity. Would you mind getting Starlight and meeting me in the other room?"
Puzzled, Twilight nodded.
A bit later, Celestia was waiting as Twilight and Starlight walked in.
"Hello, Princess," Starlight said, "You wanted to see me?"
Celestia smiled. "Oh, quite the contrary. I want you to see something. But first, we're waiting one two more..."
As if on cue (and Celestia pondered that it might have been), Discord and Fluttershy appeared in a flash.
"Alright, we're here. Now what is it, KK?" Discord said.
"Nothing serious," she said, "I just thought you might like to see this. Twilight, would you mind showing us a vision like before?"
Twilight blushed. "I guess that's alright," she said, "You just want me to show them what I showed you before?"
"Not quite," Celestia said, gesturing towards Discord, "I thought you might show us your vision of what would have happened had you sent Starlight to study with Discord."
Twilight looked between Discord and Starlight. Discord affected a bored look, while Starlight leaned in, eager to see new magic. Twilight was a bit uncomfortable with showing a scene containing ponies who were watching, but she screwed her eyes shut in concentration, trusting Celestia. Magic shot out from her horn, and a scene of a dimension with floating checkerboard balls and upside-down houses appeared.
"Oh no, it's not usually like this," Fluttershy said, "More irregular rocks, and I don't think I've ever seen more than the one house."
"Hmmm, well it depends on what you consider a house," Discord said, "Either way, far too much ground. Try this."
Discord snapped his claws and an image of his dimension overwrote the current one. The two flickered back and forth for a moment.
"Discord!" Twilight said, irritated.
Discord rolled his eyes. "Oh very well." With another snap of his claws, his image vanished.
"Thank you," Twilight said grudgingly. She screwed here eyes shut and the scene changed back to match what Discord had shown her.
"A waste of time if you ask me," Discord grumbled.
The door of Discord's house opened on its own and the view moved into it. The interior was a guess, but it was reasonably close. In the room were another Discord and Starlight.
"Discord, I have learned so much about friendship from you!" illusory Starlight said woodenly.
"Yes, and I as well," illusory Discord said in a similar tone, "I think you just might be my second best friend. After Fluttershy of course."
Fluttershy covered a chuckle with her hoof.
Celestia shot a look at Twilight. "Now, Twilight, that's not at all the sort of thing you were doing before!"
Twilight looked at Celestia abashedly. "I see now I wasn't thinking straight," she said, "And I wouldn't want to make anyone uncomfortable."
Celestia considered this. "Yes, you have a point. Starlight, may I assume you've got the basics of the spell now?"
Starlight looked surprised. "I mean I've only seen it once, but if it's a variation on Hoofdin's Glamor spell, then it shouldn't be too tough to do."
"Yes, that was my starting point!" Twilight said animatedly, "But then I added a pinch of..."
"Alouiscious's Artificial Echo!" Starlight and Twilight said at once.
"So do you want me to give my version?" Starlight said.
"Wow, Discord, I am learning so much about chaos magic!" illusory Starlight said. Her horn glowed and and a duck made of marshmallows and giant candy corns for a beak popped into existence. "Quack!"
"Yes, isn't it delightfully amusing?" illusory Discord replied, rubbing his clawed hands together.
"I do not talk like that!" real Discord protested.
"I've not talked to you much," real Starlight said.
"Now I bet I could do all kinds of things! Like... maybe turn all the buildings in Canterlot to chocolate? I bet Pinkie Pie would like that," illusory starlight said.
"Oooh, and mayhaps the streets could be milk?" illusory Discord said, rubbing his claws together. A river of milk appeared under the duck.
"Oh come now, everyone knows I snap my claws to use magic," real Discord said. He snapped his claw and swapped his limbs around, then snapped them again and turned back to normal.
"Oh, and what if we turned the mountain into a giant marshmallow?" illusory starlight said.
"Umm, I think you already used marshmallows," Fluttershy said quietly into the real Starlight's ear.
Starlight barely seemed to notice. The scene quickly shifted to Canterlot, only the buildings were melting (and made of chocolate) while ponies drowned in milk streets. An illusory Celestia and Twilight were nearby, struggling to free their wings from marshmallow.
"No!" illusory Twilight said, "How could it have come to this! If only I hadn't sent Starlight to learn with Discord!"
"Ok, I think that's enough," Twilight said, tapping Starlight on the shoulder
Starlight started, then let the illusion drop. She was visibly disturbed.
Celestia chuckled, though remembering her own pupils reaction, she kept it lighter than she had for Twilight. "Like teacher, like student," she said with a smile. "Twilight was self-conscious and full of doubt, the same as you. And you know what?" Celestia leaned in conspiratorially. "So was I."
"And we know you'd never let something like that happen," Twilight said, lightly hugging Starlight.
"Maybe back when you first came to Ponyville," Fluttershy added, remembering the mind-control incident, "But we all know you've grown since then. Starlight's upset expression slowly turned into a smile.
"Yes, yes, I'm sure this was a valuable learning experience," Discord said dismissively, "But why waste my time with this?"
Celestia looked up at Discord and smiled. "Well, I thought that would be obvious, Discord," she said. Discord looked at her skeptically. "I thought you would be able to see the humor in it."
Discord held a claw to his shin and considered that. "Well I suppose it was a bit amusing that Starbutt honestly thinks I'd leter her cause THAT much trouble. I mean, that's MY job."
"Discord," Fluttershy said scoldingly. They exchanged a look for a long moment, then burst out laughing. Twilight, Starlight, and Spike looked at them oddly.
"Did... I miss something?" Spike asked.
"Oh, we all know Discord's gotten past his bad old habits," Fluttershy said.
"Yes of course," Discord added, "I've learned to use chaos responsibly." As he said this, he snapped his claws and was suddenly wearing a monocle and tail coat and pouring wine into a glass.
Celestia chuckled lightly. "Then I guess we've all learned something today," she said with a wink, "Now, let's get back to the party before all the canapes are gone."
Author's Note
So I wrote the first paragraph and a half close to when the episode aired, then got caught up in another project. When I came back to it, I couldn't completely remember where I was going with it. It's not my best work but I think it's mildly entertaining.