This is an unofficial sequel to the Animation Equestria divided: Reunited by space oddpony,

Due to a last minute spell cast by Rarity ]in the nick of time, Twilight, Rarity, Fluttershy did not die, but they must now act quickly to defeat the cult of laughter once and for all. They may have had their final stand but with the new spell and some help, they've now got only one more chance to stop pinkie and her cult of laughter so they can restore peace to the forsaken land that is now ruined by strife and civil war.

Although, the original animation is related to mortal Kombat, the actual story and animation has little to do with it, besides the mane 6 sharing some similarities with the characters in mortal Kombat, so it will not have a crossover tag
edit 13th June 2018: added a drama tag, removed mane 6 tag and added a Fluttershy tag.

check out his guy's animations, they're really good.
https://www.youtube.com/user/DarkGuin1396/featured