Sent in by Jan Wargalla.

Sound test
 
Hold L + R on controller two and select single player 
mode with controller one. Controller two may now be 
used to start various sounds during game play.

CPU vs. CPU mode

Hold L + R and select versus mode.

Play as Hiroshi Hase

Begin game play in feature mode and defeat Hiroshi Hase 
when he appears. His character will now be available in 
versus mode.

Play as Hyper

Begin game play under the hard difficulty level and earn 
200 points during the first two matches.