Expert opponents
Select Vs. mode and set the Mode option to "COM". Hold L + R + X and press Start to begin game play. Yoshi's name will be spoken to confirm correct code entry. During game play, opponents will change color and become more aggressive.
Bonus level
Select action mode on the title screen and press Start. Set the round option to "10", the speed option to "Hi", and the music type option to "Off". Press L + R + Select + Start on controller two. Yoshi's name will be spoken to confirm correct code entry. The starting round may now be increased to include the ending and bonus levels.