User blog comment:Raheem The Dream/Manic & Sonia The Hedgehogs as DLC playable characters requested in SMASH 4 3DS/Wii U verisons!/@comment-25581315-20141103224618

If the Sonic series were to get another playable character, it would be Tails. Manic and Sonia have been rejected for the same reason Goku has. Characters originating from media outside of video games will not be in Smash. Knuckles would be a great assist, IMO.