Note: This game is also titled Shashin De Kakutou! Photo Fighter X.
At the title screen, hold Select and tap "Head Into Battle". Keep Select held and tap "Vs. mode". Your characters will now move faster.
Create four characters. Then, hold Select and tap "Vs. mode" to start a special two player battle.
Successfully complete Single Player mode to unlock a bonus song. Alternately, defeat all 100 enemies in Single Player mode.