This story is a sequel to Equestria Girls 2: Rainbow Rocks

Sunset joins the Chaos Rainbooms after she helped her friends defeat the sirens after her long way of being a bully at CHS, everyone finally trusts Sunset Shimmer and not only that, but her and Shadow are true friends again. After all of that, today is the competition against CHS’s rival school, Crystal Prep Academy, a school that beat CHS multiple times in a competition called the Friendship Games.

The Chaos Rainbooms thinks it’s time for a change and that they aren’t going to lose to Crystal Prep and were determined/ready to win, but to their shock, they saw Twilight and two of her friends they don’t know about, but Sunset, Rainbow, Fluttershy, Rarity, Pinkie, and Applejack must not “pony up” or else that would be considered cheating according to Vice Principal Luna.

This story is a sequel to Sonic & Friends in Equestria Girls

After Sunset’s and Metal’s defeat, a few weeks has passed and no students forgiven Sunset after the Formal Fall and the times she treated everyone, except Applejack, Pinkie, Rainbow Dash, Rarity, Fluttershy, Cream & Cheese, Shadow (kinda), Rouge, and the Chaotix.

Shortly after, 3 new students showed up to CHS and as Sunset, Cream & Cheese show them around, that day was the “Battle of the Bands” and something was off about them after the students began arguing with each other and both principals acted really strange, so Sunset grab her book given to her by Celestia and asked her for help.

While Twilight was on her adventure, she was given a book that was glowing purple and it was Sunset asking for help so she, Sonic, Tails, Knuckles, Amy, and Spike go back to the other dimension to save their friends.

After putting the two powerful artifacts close to each other, it doesn’t go well.

Both the Elements of Harmony and the Chaos Emeralds flew off all of Equestria. So the Mane 6 and the Dreamcaster go off on a big journey to make new friends, make new rivals by accident along the way and even find some secret places.

But since the Chaos Emeralds and Elements of Harmony caused them to scatter, a some new/old and unknown bad guys come in for example: Bowser and Dr. Neo Cortex, including friends for example: Mario Brothers, Yoshi, Kirby, and Crash Bandicoot. (These characters are important, but I can only put 3 series tags)

P.S.: Violence because of fight scenes

After the defeat of Queen Chrysalis and King Sombra, and Twilight becoming an alicorn and new princess, The Mane 6 and Spike send an invitation to Sonic and friends so they can celebrate with her. All things are going well, until a mysterious pony steals Twilight’s crown and escape into a portal, which leads to a different world. Making no hesitation, Sonic jumps in first as Tails, Amy, Twilight, Knuckles, and lastly Spike following along.

The new world they ended up in was completely different from Equestria, but the big change was that Twilight was a human. Sonic, Tails, Amy, and Knuckles were that same, except they were taller now. And Spike was a dog. With these changes, they must face school itself in order to get the crown back.