Configuration mode...
	Debug Menu...
	Fight against the CPU in Duel ...
	Fight The Bosses...
	Hidden Option Mode...

Start match and finish the fight. Hold R + X + A at the continue screen until the next match starts. The configuration mode screen will appear.

After choosing a character, hold R + X + A. The debug menu will appear before the round starts.

Hold L + R on the character selection screen to control the other player's selection. Hold L + R and press Y to select your opponent's character. That character will be CPU controlled at the current difficulty setting.

Highlight the "Story Mode" option, then hold L + R and press Start.

Start a one player game, and press X + A + L when the fighter's names are displayed.