It is a special day in Canterlot as the mane 6 along with Starlight glimmer celiberate Princess Celestia's birthday but when an evil pony comes and captures all of the princesses it's up to Starlight to make the most important decision of her life
Nightmare Amy interups Sonic, Rainbow Dash, Shadow and Sunset's wedding and takes the main six away and transports them to diffrent locations in Equestria.
It's been two years since Sonic and Shadow have been to Equestria and now they are on their way back to see their new friends but an old enamy awaits their return
Discord escapes from his stone prision and stells a gem called the gem of power. Because of this princess Celestia and her sister princess Luna have to summen help from another dimension. So they find Sonic and Shadow and bring them to thier world