As the trailer begins, we see a blue blur running through a letter. The blur runs through it again and a famous tune is played.
The screen fades into black and were now seeing a firework as two words appear
The screen fades into black and were now seeing a blue head of a hedgehog and white words as a voice and a sound of a ring is heard.
Sonic Team Presents
The screen fades into black again and the trailer now officially begins
SEGA, Hasbro Studios and Sonic Team Presents
Were seeing a bright yellow explosion in some sort of a green hill.
The scene changes to the Town Hall where the mayor is making a speech to a crowd of ponies
Mayor Mare: Fillies and gentlecolts, the good news is that Discord was defeated by Twilight and her friends!
In an alley, the shadows of two figures cast on a wall, projecting the image of a unicorn shooting someone else with his horn.
The scene changes to the Golden Oaks Library, where Rarity stands next to the weakened and exhausted Twilight.
Rarity: Ponies all over Equestria are disappearing, including Rainbow Dash.
In the Sweet Apple Acres, Rainbow Dash is suddenly engulfed in yellow energy and vanishes right in front of Applejack's eyes, only for the blue Pegasus to be replaced by
At Spagonia, Tails and Amy were having a conversation at Spagonia University.
Tails: Many people here in Spagonia and some other cities have also disappeared.
The scene then changes to Ponyville where Fluttershy stares at the portal for a moment.
Shadow: CHAOS CONTROL!
Fluttershy tried to flee, but she was suddenly frozen and Shadows hand grabs the Pegasus by the tail and drags her into the portal. The scene then changes to Cloudsdale where Applejacks voice is heard.
Applejack (background): Equestria is in the process with mergin with another world.
The scene changes to the Flame Core (Sonic 06s stage), where Mephiles is being freed from the prison. And then, changes to the Golden Oaks Library, with Metal Sonic and a weakened Tails.
Metal Sonic: But our abilities are growing stronger as a result of the merging.
The scene now changes again to Ponyville, where Shadow fires a Chaos Spear at Twilight, sending her crashing into a wall of a house. She looks over her body as electric bolts disappear.
Twilight Sparkle: Magic powers?
The scene changes to Sugarcube Corner where Mr. and Mrs. Cake stops a fight between Pinkie Pie and Queen Chrysalis.
Mrs. Cake: The merging of the worlds is contaminating Equestria.
The scene changes to Shadow and Rarity in a merged Canterlot with Stardust Speedway. And then changes to a conversation between Sonic, Tails, Blaze and Silver at Soleanna.
Sonic: Mobius must be facing a great new challenge.
Fluttershy flies through Ponyville. And then, Applejack informs Rarity through her
Element of Generosity as she walks in Canterlot.
Applejack: Our world and the other world are occupyin the same time and space.
The scene changes to Spagonia, where Queen Chrysalis is flying to a battle. And then, changes to the Crystal Empire, where we see Sonic and Knuckles. Sonic was touching the Crystal Heart with one hand while in the other hand, he was holding a blue Chaos Emerald.
Sonic: The powers are shifting, rebalancing
Blaze was about to finish Pinkie Pie, when Fluttershy intervenes and punches her. The scene then changes to a strange place with the MLP group while Applejack was talking with them.
Applejack: Grindin two universes together will eventually rip them both apart.
The scene now changes to the Flame Core where Mephiles is freed from his prison.
Mephiles: Light Gaia must have underestimated me.
The scene quickly changes to Soleanna with Sonic, Tails, Knuckles, Mephiles, Amy, Shadow, Metal Sonic and Captain Whisker.
Amy: At first, I thought it was the Egghead, but actually, it is someone much more powerful
Gilda laughs madly at the streets of Manehatten.
The scene changes to Sweet Apple Acres where Knuckles confronts Applejack as they circle around each other.
Applejack: Yer world is invadin mine, affectin everythin and everypony in it.
Shadow teleports away from an unconscious Rarity.
Amy: Bitter rivals must fight as one.
The scene changes to Sonic, Tails, Knuckles, Amy, Shadow, Blaze, Silver, Metal Sonic, Captain Whisker and Jet walking in the right side of the center of the Death Egg, while Princess Celestias voice is heard.
Princess Celestia (background): You must gather an army of both dark and light.
The scene now changes to Twilight, Applejack, Rainbow Dash, Rarity, Fluttershy, Pinkie Pie, King Sombra, Queen Chrysalis, Trixie and Gilda walking in the left side of the old castle from the episode Friendship is Magic, part 2.
The scene changes to all of STH characters reunited with Sonic at Soleanna.
Sonic: If we fail, none of us will survive.
Applejack is seeing Equestria merging with another world through the window in Cloudsdale.
Applejack: It is gettin worse than I suspected. Much worse.
At the Golden Oaks Library, Pinkie Pie, now with her grayish pink coat and deflated mane, uppercuts Tails, sending him flying by Twilights unconscious body and slamming hard into the floor.
The scene changes to a floating asteroid where all STH and MLP characters are facing each other and get ready to battle.
Sonic: We came here to challenge you to a fierce combat!
The characters of both universes let out their battle cries and charge towards their opposition, except for Twilight and Sonic, who remain in their spots and glare at one another.
Gilda roars at Silver trying to paralyze him, but Silver continues to approach her due to Kombat Rage.
Blaze slash with her claws at Queen Chrysalis various times, and then kick her various times before sending a fireball at the changeling.
Knuckles uppercuts Twilight and uses Thunder Arrow at her, and then punches her many times.
In close combat, Captain Whisker uppercuts Pinkie Pie in the face, and then punches her in the stomach.
In freefall combat, Twilight punches and kicks Sonic many times before charging up her horn with her magic and shoot at Sonic, sending the blue hedgehog towards the ground fast.
SONIC THE HEDGEHOG VS. MY LITTLE PONY UNIVERSE!
The scene changes to Gilda, King Sombra and Queen Chrysalis at Ponyville, with Gilda pleading to the former ruler of the Crystal Empire to join her.
Gilda: Come on! Lets make some pranks, kill things, and blow things up! This will be FUN!