Arcade Backgrounds
     Let the time runout in the Stage Select screen.

Change Backgrounds in Training Mode
     Before selecting a stage, hold Start and press A.

Play as Gold Dural
     At  the  Character  Selection screen, and in training mode, press
Start + Y + A.

Play as Silver Dural
     At the Character Selection screen, press Start + X + A.

Fight Against Alphabet Character
     At  the  Character  Selection  screen,  highlight Akira and press
Start.  Then  highlight  Lau  and press Start. Now highlight Pai, hold
Start and press X.

Fight as Alphabet Character
     At  the  Character  Selection  screen,  highlight Akira and press
Start.  Then  highlight  Lion  and  press Start. Now highlight Pai and
press Start. Finally, select any character and press A.