First Enter NPLAYERS as your name . Then, From the Main Menu, go to the Track Select screen. After you have selected a track you will now be able to select the number of competitors.
Racing Bonus Track
To play on a track which resembles a racing track from Ridge Racer, enter RIDGERACER as your name in a two-player game.
Ruins Bonus Track
To play on the Ruins bonus track enter REFLECT! as a name.
Take No Damage
Enter !DAMAGE! as your name. You will not take damage while playing
Choose Number of Enemies ...