...It was...
"Sonic Gems Collection?" Applejack asked. "Now why would Rarity put this in a..."
The farmer then realised. It was a 'gem collection' in a chest! She burst out laughing litres of joyful tears.
"Oh.. My... I get it!!" She then burst out again. She was rolling on the floor, and--
"WHAT DID YOU DO TO MY SISTER?!!"
Applejack turned around to see Sweetie Belle there. At first AJ didn't know WHAT was up. Then, right next to her hooves, was the white unicorn, unconscious.
"GOT YOU!!" Rarity shouted as she jumped up, scaring Applejack.
"Woah nelly, nice one, Rarity! Y' really got me!" Applejack said.
"Wow. That was a sure funny joke. Hahaha!"
Rarity went over and picked the game case up with her magic. "Who's up for a game of Sonic Gems Collection?"
I hope you liked this story. I put a teeny bit of seriousness into it, but I think it turned out alright.