AFTERIMAGE Mode
Beat the game with everyone on the same saved file. Go to Options. Go to Bonus Modes. You will Have No wall mode, No gauge mode, etc. You also have Afterimage near the bottom of the menu turn it on and get into a fight with a friend or with the computer, you just fight each other and see what happens.
Unlock Codes
Beat the game with everyone on level 4 or higher and you will get all the codes. in time attack mode, beat the game with allice under 10 minutes and you will get to play allice in her school uniform.