A Link Between Destinies

Twilight and the rest of the gang couldn't believe what they just saw, Rainbow Dash vanished out of thin air. Pinkie Pie even grabbed a megaphone and shouted, hoping that Rainbow Dash was hiding in a cloud or some sort of cruel prank to scare them.

"RAINBOW DASH! WHERE ARE YOU!?", shouted Pinkie Pie using the megaphone, creating winds strong enough to push a small colt.

Twilight approached Pinkie Pie and tried to calm her down.

"Pinkie Pie, I think she's gone", said Twilight in a sad tone.

"Gone where? Where is she? Tell me!"

Pinkie Pie started freaking out, thinking that she had just lost one of her best friends.

"Gone into the dark realm", said a mysterious voice that surprised the five ponies.

All of them turned around and saw Princess Celestia coming from straight from Canterlot's palace. She landed next to the five ponies on the hill, looked at the orb of light and then spoke.

"Rainbow Dash isn't gone, but she does need your help"

"What do you mean by that, princess?", Twilight.asked

"It seems like the Sonic Rainboom triggered some sort of residual magic. This magic seems to be extremely unstable, so it opened a rift that your friend seems to have crossed."

"A rift? Like something that allows you to cross dimensions? Does that mean that Rainbow Dash is in another dimension?", Twilight asked again.

"Yes. That orb of light you can see there is the rift still open, if we're lucky, we might be able of opening it again so one of use can cross it and save Rainbow Dash."

While she explained what had just happened, Celestia used her magic on the orb of light and it started freaking out. Eventually, the orb expanded, creating some sort of portal.

"Now, only one of us can go, and it must be a unicorn so that you can open a portal from the other side, that's your only way of getting back."

"I'll go", Twilight said as she took one step forward.

"Rainbow Dash is counting on us, so we need to hurry"

"That is very noble of you, Twilight, but are you sure you're capable of coming back?" Celestia asked to her pupil, hoping to get the right answer.

"All I know is that we can't just sit here waiting for something to happen. Rainbow Dash has saved us countless times, we can't just let her down like this.", said Twilight in a more assertive tone.

"Very well, I shall keep this rift open for you as long as I can, don't waste this opportunity"

"Understood. Fluttershy! I need you to carry me up there so i can cross the rift."

"Okay, I'll do it if that's ok with you."

Fluttershy grabbed Twilight and lifted her up into the sky. Fluttershy was struggling because she wasn't used to carrying anything heavier than a critter, but she didn't just gave up and pulled harder, eventually ending up right over the rift.

"Are you ready, Twilight?"

"Yes, let me go!"

Fluttershy then dropped Twilight and she began to fall. She almost missed the rift completely, but she managed to touch it and, by doing so, crossing it into the other side...... into the Dark Realm.