Secret options:
Go to the Menu Screen. Press and hold L1 + R2 + Square + Left Do this until "Cheat Mode" appears under Options.

Unlimited lives:
Pause game play and press Right, Square, Triangle, Square, Triangle, X.

Nude color scheme:
Beat the game under each difficulty setting. Play the game again under the Hard. Enter NUD as initials after completing the game.

Block Throws:
When your enemy has you in their grasp and are ready to throw you, you can counter their action by simply tapping the punch button. This will stop them from throwing you, and allow you to punch their lights out.

Cheat Menu:
At the main screen (1 PLAYER, 2 PLAYER, and OPTIONS) hold Left + Square + L1 + R2 until "Cheat Mode" appears at the bottome of your screen. Quickly choose OPTIONS and you can enable Invincibility or start on any level.

Easy Bazooka:
In the start of the game you will see a car on the left. Go to the back of it, then punch it until it explodes. After it explodes, pick up the bazooka that dropped out.

Easy Gun and Metal Stick:
In level one, after destroying the police go to the upper-right corner, near the gate and you will find a metal stick and a gun.

Easy Shotgun:
In the first level, destroy the car near the ending doors in the parking lot and a shotgun will fly out of the back.

Easy Victory:
To defeat a boss or enemy with ease, just tap the punch and kick buttons at the same time. This will give you a soccer style kicking maneuver. Repeat until the boss or enemy is dead. If you have a turbo controller you can simply put the punch and kick buttons on auto, allowing you to just hold those buttons.

Get Shotgun or Handgun after Beating a Level:
When you beat a level and see the destruction bonus etc, hurry to the exit. If done correctly you will hear a chome! and the screen will flash white for a second. When you go to the next level you will either have a shotgun or a handgun. If playing two player, first player will have the shotgun and second player will have the handgun or vice versa.

Mega Gun:
Go to the air base. Once inside go over to the hanger, and bash the A-10 for a while,and its gun will fall off. This huge gun which even the big guy will struggle to lift, is a devestating weapon.

Secret Move:
To do a secret move with any of the four fighters, quickly move your thumb from Circle to X. If done correctly here is what each fighter should do:

Smasher: Earthquake pound
Alana: Sweep
Mace: Sweep
Hawk: Jumping spin kick

Super Combo:
With Hawk, grab someone and then press X, X, X, Square, Square, Square, Triangle. This combo can kill most characters and is the best grab move in the game.

Unlimited Lives
To get unlimited lives, pause the game and press Right, Square, Triangle, Square, Triangle, X.