A saiyan in Equestria?

"So when does the job start?" asked Ato who had just been awarded the position of a knight of the Equestrian force.

"I'll contact you if something happens, you're free to go for now." said Celestia

"Wait, but how?" asked Ato,

Celestia put her hoof on Ato's head and it radiated a blissful energy.

"That my pupil, was a psychic link, so I can communicate with you through our thoughts." said Celestia

"Thanks for all of this, really." said Ato gratefully

"It's not a problem, and before you go, take this." Celestia handed him the Equestrian force badge

Ato flew back to Ponyville, ready to tell Dash of his success.

"Hey Rainbow Dash, I got the job!" said Ato happily

"Great, but I need to ask you something." said Dash

"So basically this thing, er group, they're called the Wonderbolts, and I really wanna be part of it and you have to try out for it-" said Dash

"and you want me to help you train?" predicted Ato

"Yeah pretty much. Hey wait, you still don't have somewhere to live do you?" said Dash

"D'oh! Ato faceplanted "Yeah, I guess I hadn't thought about it..." said Ato

"Hey don't worry about it, if you help me train, you can crash at my place, deal?" proposed Rainbow Dash

"Deal." he replied

And so they started training vigorously, testing eachother's limits, pushing both of them harder each day.

In terms of speed, Ato was faster than the eye, but in comparison to Dash he was slow as molasses.

Then the day came, the Wonderbolts tryouts

"Well this is the day. Good Luck out there Dash!" said Ato

"Thanks! I'll try my best!" said Dash excitedly

"By the way, tryouts are private, so you can't come, sorry." said Dash apologetically

"Don't worry about it, I understand." said Ato

And so she went alone to the tryouts, nervous, but determined.

"Alright Wonderbolts, my name is Rainbow Dash and I'm here to show my AWESOME talent, flying! Any questions before I blow you away?" said Rainbow Dash confidently

"Wait,"a wonderbolt chuckled, "you're Rainbow Dash, the one hanging out with the freaky alien?"

"Oh I know which one your talking about, the one that looks like a monkey with clothes?" said another Wonderbolt

"Dude, do you like, not have like, pride, I mean like, hanging out with that thing?" said yet another Wonderbolt tauntingly

The insults slowly turned into a whole gossip session until Dash finally spoke up

"HEY! I'll have you know that "freaky alien" is my friend, and through experience I have learned that a good friend doesn't insult another friend, so why should I be friends with you guys? I wouldn't wanna be one of you Wonderdolts if it meant hanging out with you jerks!" said Rainbow Dash

What followed was a long silence until a wonderbolt broke it and said:

"Get out."

Dash left learning an important lesson that day, and had no regrets.

"Did you make it?" Ato asked once Dash arrived home

"Nope, but I think I'll be fine."