A world of peace is now a shadow of its normal self as Terra is in a war with a returned King Sombra and has taken control of the Crystal Empire and declared war on Equestria. But when Twilight and her friends try to stop him the evil king put a powerful spell over them corrupting them turning them into Chaos Demons which are similar to Discord. Then Sombra puts Princess Luna and Celestia into a deep hibernative slumber and seals them away along with the Crystal Heart in a spell created prison.

Now four years later the CMC now almost at the age of the Mane 6 are searching for a cure that can break the spell that Sombra has on their six friends, but Scootaloo, Sweetie Belle, and Applebloom soon find a new spark of hope when three stange stallions which are two unicorns and one Pegasus from another world. These three aren't just any stallions they are Sonic The Hedgehog, Shadow the Hedgehog, and finally Silver the Hedgehog who have been sent to Terra by the 7 Chaos Emeralds which are now scattered around the world.

Now with new friends and allies Sonic and his two friendly rivals must find the Chaos Emeralds, save world from darkness, free the Mane 6 from Sombra's control, free Luna and Celestia from their icy prison, and defeat Sombra once and for all! Sonic may have beaten Eggman's plans every time, but this time he's got to get his A-game on overdrive to stop an evil king!

All Sonic Characters have their Sonic X voices.

Sonic The Hedgehog is owned by Sega.
MLPFiM is owned by Hasbro Studios.

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