Complete the game to unlock the "Continued Play" option, which allows a new game to be started with all previous stats and items, and an alternate main menu background (with characters from the game). Complete the game on Medium difficulty to unlock additional missions that can be played with any character.
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 recommended to have a fast recovery of health. Use the Speed Boosts in all the recovery slots.
Press Start to pause game play. Then, hold L + R and press DOWN, LEFT, UP, RIGHT to enable cheat mode. This will also unlock all costumes. Activate the following cheats by pausing the game and pressing the corresponding sequences of buttons:
CHEAT FUNCTION - CHEAT CODE Invincibility - Hold L + R and press LEFT, DOWN, RIGHT, UP, LEFT, DOWN, RIGHT, UP. Infinite Superpower - Hold L + R and press DOWN(2), RIGHT(2), UP(2), LEFT(2). Maximum abilities - Hold L + R and press RIGHT, DOWN, RIGHT, DOWN. 35 random boosts - Hold L + R and press LEFT, RIGHT, LEFT, RIGHT. 20 shields - Hold L + R and press UP(2), DOWN(2). All costumes - Hold L + R and press DOWN, LEFT, UP, RIGHT.