Sonic The Hedgehog x My Little Pony: Make Your Mark - Season 4: Revisited | Teaser · 4:12pm June 8th
In the middle of a field, near a canyon, Sonic the Hedgehog and Sunny Starscout advanced with frowns in their faces, Sunny having her Alicorn form activated.
Soon, the rest of their friends follow ahead: Tails, Knuckles, Amy, Shadow, Rouge, Omega, Izzy, Hitch, Sparky, Zipp, Pipp and Misty. But not only them: Eggman and Sage also arrive, the former one panting exhausted from running, before panicking at the sight ahead, while everyone else looked either concerned or with frowns.
In front of them, a giant creature that looked like a corrupted version of an Ancient: It was a black creature with red veins all over their body, 8 fin-like protrusions on the back of their head, a tall bulge on top, and 8 red eyes. They also have a red aura surrounding them, as well as a strange red symbol floating behind them, which works as the wings of this creature. Finally, they had one single leg that looked like a sharp sword.
Sonic then was surrounded by the Chaos Emeralds and elevated in the air by them before they fused with him, turning him into Super Sonic, who looked ahead with a determinate look, making everyone else nod and look ahead as well.
However, Sonic didn't stopped there, as he got surround by a red aura that powered him up, blue electricity surrounding him. When he opened his eyes, instead of being red, they were blue now, meaning a new power has been unlocked.
THERE'S ALWAYS TWO WAYS TO TELL A STORY
SONIC THE HEDGEHOG X MY LITTLE PONY: MAKE YOUR MARK - SEASON 4: REVISITED
November 10
Nice! I am so looking forward to it!
Is it alright if THIS is The End's true form in this story? If not, that's fine. Just a suggestion:
The End (Ultimate Form) by Hexsmasher on Deviantart
Basically, it's adding on certain things to what you described, like the extra arms and what they're using in this piece, and actual wings protruding from its back, for example.