there is no backgrounds im pretty sure and there is only one background
You have to earn 2500 star fruits and go on dojo sensei's swag go on the last one and cut skip challenge
I don't have a clue
Playing a lot
You have to unlock multiplayer.
unlock it in practice mode
No. You'll have to buy it separately.
You unlock it by typing in the last 4 numbers of your phone number.
To get the last character ( Ras Al Ghul ) you must first spend 4 billion studs to unlock the last data piece.
Depending on how you unlock them, possibly.
it is shyguy you can unlock him when you play mariokart DS download play
the last character you can unlock is doctor boskonovitch
Play 400 brawls and unlock all the characters.