Mario
there is no main character
You don't, because the Mii isn't a playable character. The Mii, however, will be a playable character in the next Super Smash Bros. games, Super Smash Bros. for Wii U and Super Smash Bros. for Nintendo 3DS.
What character?
The fastest playable character in Super Smash Bros. Brawlis Sonic the Hedgehog.
No, Jack Skellington is not a playable character in Super Smash Bros. Brawl.
Shadow is not a character in Super Smash Bros Brawl, unfortunately.
Master hand is not a playable character in any of the smash bros games.
Video game enthusiasts know Ganondorf as a main villain from the Zelda and Link video games. The character has even crossed over into other games such as Super Smash Bros. Melee and Super Smash Bros. Brawl.
Yes, he will be a playable character in Super Smash Bros. for Wii U and Super Smash Bros. for Nintendo 3DS (both of which are Super Smash Bros. 4).
No, Raichu is not a character in Super Smash Bros Melee and is unplayable
Super Smash Bros Brawl Main Theme.
mewtwo is not in super smash bros. brawl however mew is a trophy character