Type in the enable code at the main menu. A chime will sound.

Right, Right, Left, Left, Right, Left, Right

Then type in one of the following codes
(Must type in the enable code before each one) Another chime will sound if entered correctly.

Xena can fight Gabrielle instead of Hope
C-Left, C-Left, C-Left, C-Left

Play as Dispair
C-Left, C-Right, C-Left, C-Right

Play as Dispair in a bunny suit
C-Left, C-Up, C-Right, C-Down

Enable Titan Mode (Fight three people in quest mode)
C-Up, C-Down, C-Up, C-Down