Highlight a fighter and press Up or Down at the character selection screen.
Full pause screen
Press Start to pause game play, then press X + Y.
Play as B.M.
Defeat B.M. in arcade or random mode with a Super K.O.
Play as Del Sol
Defeat Del Sol in random mode and complete the game. Del Sol will randomly appear as Tokio's first opponent.
Play as Kuhn
Reach and defeat Mahler in arcade mode in less than 5:50 with at least half of your strength remaining or a Super K.O. Then, defeat Kuhn in the bonus stage.
Super Kick
Hold Back and press the Kick button
Super KO
If you lost all your armor, hold Forward and press the Punch button, the Guard button, and the Kick button all at the same time. I have NO idea what will happen. Maybe your opponent will blast to God knows where! Or your opponent will go BOOM :)
Note: If you do this with your armor still on, you will make a dome from electricity... hmm :)
Super Punch
The same thing, but this time press the Punch button instead of the Kick button.