After you win a match and your character does his/her victory pose, press Start. You'll be able to attack your fallen opponent while he/she is down.
Fight Secret Characters
Evil Sakura - Perform 5 Team Super Finishes
Evil Zangief - Perform 6 Team Super Finishes
Shadow Charlie - Perform 7 Team Super Finishes
Fight Secret Characters (Japanese Version only)
Fight Mech Zangief: Perform 3 Crossover Combination finishes and 2 Hyper Combo finishes. Fight Dark Sakura: Perform 4 Crossover Combination finishes and 1 Hyper Combo finish. Fight Shadow: Use the Swap Trick (holding 3 punches before the fight starts) in EACH battle (including the battle 6), get a "First Attack" in Each battle and finish 4 battles with a Crossover Combination Finish and the last one with a Hyper Combo Finish or a Crossover Combination Finish.
Play as Evil Sakura
Hold Start, move to Hulk, hold Right at least five seconds then press Jab+Fierce or Short+Roundhouse.
Play as Mega Zangief
Hold Start, move to Blackheart, hold Left at least five seconds then press Jab+Fierce or Short+Roundhouse.
Play as Mephisto
Hold Start, move to Omega Red, hold Down at least five seconds then press Jab+Fierce or Short+Roundhouse.
Play as Shadow Charlie
Hold Start, move to Dhalsim, hold Up at least five seconds then press Jab+Fierce or Short+Roundhouse.
Play as Spider-Man (in Spider Armor)
Hold Start, move to Ryu, hold Down at least five seconds then press Jab+Fierce or Short+Roundhouse.
Play as U.S. Agent
Hold Start, move to Bison, hold Up for at least five seconds then press Jab+Fierce or Short+Roundhouse.
Switch starting character
Press Start and the three punch buttons at the same time after choosing your characters. Hold it until the match begins. You will begin fighting with your second character.