When Ellis starts dancing press Up, Down, B, A, Right, Left, B, A to get every character including Gaia, Gaia 2, Uranus, and Sho.
Fight As Gaia, Gaia II, Uranus, Or Sho
Turn on the game. When the dancing demo appears press Up, Down, A, B, Right, Left, A, B.
Fight Gaia II And Sho
Enter the "Play as Gaia II or Sho" code, then choose either the normal setting or hard setting and play as Sho in the 1-player game. If you chose NORMAL you'll fight a random opponent, but if you choose HARD you'll fight Gaia II and Sho. I wonder what happens in EXPERT mode?
Jet Mode
To get Jet Mode, press Up, Up, Select, A, Up, Up, B at the title screen. This will make the CPU character go much faster.
Play As Gaia II Or Sho
When the TAKARA logo appears, press SELECT three times. When Ellis appears press Right, Left, A, B to get both Sho and Gaia II.
Read All Dialogue
When the Takara logo appears press B, A, Left, Right, B, A, Down, Up, B, A to view every characters dialogue including tips and special attacks.
Scorcher Mode
When the Takara logo appears press Select three times to get into scorcher mode. This lets you do special attacks.