Cheat mode
Press Start to pause game play. Then, hold L1 + L2 + R1 + R2 and press Down, Left, Up, Right to enable cheat mode. This will allow the other codes to be activated, as well as unlock all costumes.

Invincibility
Press Start to pause game play. Then, hold L1 + L2 + R1 + R2 and press Left, Down, Right, Up, Left, Down, Right, Up.

Unlimited Superpower
Press Start to pause game play. Then, hold L1 + L2 + R1 + R2 and press Down(2), Right(2), Up(2), Left(2).

Maximum abilities
Press Start to pause game play. Then, hold L1 + L2 + R1 + R2 and press Right, Down, Right, Down.

35 random boosts
Press Start to pause game play. Then, hold L1 + L2 + R1 + R2 and press Left, Right, Left, Right.

20 shields
Press Start to pause game play. Then, hold L1 + L2 + R1 + R2 and press Up(2), Down(2).

Bonus heroes
The following characters can be unlocked by spending the indicated amount of Justice League of America shields that can be collected during game play.

Aquaman: 27 shields
Green Arrow: 76 shields
Green Lantern (Hal Jordan): 84 shields
Green Lantern (Kyle Rayner): 55 shields
Hawkgirl: 70 shields
Huntress: 53 shields

Alternate costumes
The following characters can be unlocked by spending the indicated amount of Justice League of America shields that can be collected during game play.

Batman (classic blue): 59 shields
Batman (Batman Beyond infiltration suit): 74 shields
Flash (Jay Garrick): 21 shields
Flash (Walter West): 48 shields
Green Lantern (retro): 23 shields
Green Lantern (bold): 30 shields
Martian Manhunter (modern): 29 shields
Martian Manhunter (true): 15 shields
Superman (black recovery suit): 32 shields
Superman (Earth 2): 65 shields
Superman (Kandor): 91 shields
Wonder Woman (biker): 61 shields
Wonder Woman (toga): 44 shields
Zatanna (classic blue): 25 shields
Zatanna (Identity Crisis): 38 shields

Completion bonuses
Successfully complete the game to unlock the "Continued Play" option (to allow a new game to be started with all previous stats and items unlocked" and an alternate main menu background (with characters from the game).

Fast health recovery
Upgrade your health recover and the strongest weapon for the character you are currently using. For example, upgrade the Flash's Whirlwind ability or Wonder Woman's Tiara throwing ability with Damage and Duration boosts. All the characters lose health quickly to most any kind of attacks. It is wise to have a fast recovery of health. Use the Speed Boosts in all the recovery slots.