Sonic Vs. My Little Pony 2A: Clash of Both Worlds is a crossover fighting games developed and published by Nintendo featuring the characters from Sonic series and MLP series. This is the second installment since Sonic Vs. My Little Pony and the second series on the Super Smash Vs. Cartoon Alliance (series). It'll feature more characters and two OC characters.
After the defeat of Dr.Eggman and Discord, a new danger is coming on both worlds. When Mephiles and Sombra created two dimensional portals in the same time, it's causes catastrophe on Mobius and Ponyville. Not only that, the portals lure the two enemies and merged together into a powerful fusion, Sephra.
The Mobians and the ponies collide together. Due to the thanks for the Mobians stopping Discord and Eggman conquering on Ponyville last time, the two groups decided to form an alliance in order to stop Sephra and the portals. However, two new heroes joined in. But, they're not actually from their current time.