"Rainbow Dash temporarily swaps AJ and Rarity's minds and gets away with it scott free."
Rainbow Dash shorted in front of Discord. "There! I've worked as Fluttershy's personal maid for a week of compressed time in Chaosville! Now you hold your end of the bargain!"
"Are you sure you don't want to for another week?" Discord grinned.
"Ugh! No way! I've seen this movie! I am NOT growing to like that! At least wearing the maid uniform this time wasn't as bad as when I lost that bet to Soarin'."
"Bad as in you didn't enjoy it, or you enjoyed it too much?"
"NOT TELLING!" Rainbow Dash blushed.
"It was your fault for challenging him to a pie eating contest," Discord said like a parent.
"Whatever! Just give me the magical dodad!"
"It's not a dodad, it's a dohicky, please keep them straight." Discord gave placed a glowing swirling colored sphere in Rainbow Dash's hooves. "This looks the same as the others I've gotten from you."
"And I keep telling you, I magically alter them to be different... it's how I cover my tracks... no one would suspect macguffins from Discord to look the same after all. A temporary mind-swap spell with a 'deflect probable blame' enchantment thrown in. Now have fun!" Discord snapped his fingers.
Rainbow Dash was instantly back in Ponyville, right outside Rarity's shop (Rainbow Dash never could spell its name).
She peaked inside, and as Discord had provided, there was Applejack and Rarity. Rarity wanting notes from AJ on how to make a 'rustic be elegant' dress for middle class ponies. And AJ looking bored.
"Time for the fun!" Rainbow Dash raised the orb, that flashed random colors (including few that ponies had no name for), and vanished.
Rarity and Applejack shuddered, and gasped. Then looked over themselves in surprise, then alarm, then sighing in frustration.
"Again?" Rarity sighed in annoyance in Applejack's body.
"Again," AJ said in Rarity's body.
Rainbow Dash frowned.
"Just promise me this time you won't get my dress covered in mud trying to square dance at the Canterlot social this time."
"If ya promise not to spent more time tryin' ta stack up apples all nice and pretty."
"Oh come! At least give a 'THIS IS THE POSSIBLE THING!' in AJ's voice!" Rainbow Dash exasperated... then covered her muzzle.
AJ and Rarity turned right at her, their eyes narrowing... then shuddered.
"You know who is obviously behind this Applejack?" Asked Rarity-in-AJ.
"Who ya think' Rarity?" AJ-in-Rarity replied.
"King Sombra!" They said together.
"Ah know he was up ta no good again! Let's give'em a piece of our minds!"
"I couldn't agree more darling!"
----
"And that is how you have a successfully and happy marriage even when you're an evil overlord," King Sombra said behind the podium.
Various evil, and single, dark overlords sitting in the various auditorium seats.
The doors were flung open, the goblins hired to serves as bouncers out cold.
"KING SOMBRA! YOU'LL MAKE FOR SWITCHING APPLEJACK AND MY MIND!" Rarity-In-AJ shouted dramatically.
"What? ... I haven't done anything even evil today! Radiant Hope just finished resurrecting me, again."
"Yer lies won't save ya!" AJ said, and the two mares charged.
Radiant Hope signed and got the resurrect spell ready again.