Hold L1 + L2 + R1 + Triangle + X + Left when "Press Start" appears at the opening screen. Select "Start Game" option and choose a level. Your character will have unlimited ammunition and invincibility during game. (Note: Enabling Cheat disables high scores.) 

Invincibility/Infinite Ammo
At the title screen, press the following - L1+L2+R1+X+Triangle+Left - You'll automatically be taken to the game screen.

More rage - Pulverize a vending machine until sodas fall out. Then stand over a can and press X.

Hints: 

Do not worry about the last stage when you have limited health and ammo that final level is so tricky that it took me a day to finish that level and got up to the cyborg life form but i found a way to defeat him.

Easy Battle - Cyborg Life form:
first of all don't go near him and avoid him at all times otherwise he will fire bolts at you from his hand weapons are useless here nothing can kill him because he is invincible so all you can do is to run to the green energy columns and wait until he catches up with you when he turns into his monster form the door will unlock and you can go through it once you reached the computer console go up to it to fire a charged up laser beam this is the only effective weapon that can harm him use the target circle to aim the beam place the circle anywhere you can move it around sometimes he gets near the console if he gets close enough he will fire bolts from his mouth if the cyborg life form gets near then get off the console and lure him to a corner and get back on the computer again more laser hits will destroy it.

Research lab - Secret Areas:
I found two cool secret areas in the Research Lab level the first one is located in a large room with a computer map on the wall if you shoot or kick it you will find power glove and some other items the second secret area is in the next section of the level but its inside the metal grid entrance you can shoot it with a well aimed pistol shot avoid the mines and cross the ceiling ladder go up the second ladder you will find a really cool rocket launcher and iron bars plus some supply cupboards.

A Beginners guide to this game:
Tricky levels can be a pain in the neck sometimes don't worry about this game if you happen to run out of continues and have loaded a last save you can go back to that level and start a different strategy if you are not much of a pro you can read the manual to get combat moves hints and tips to stay alive and your own strategies.

You can use any cheats you like but there isn't much for this game because finding something to old or new won't get you anywhere but the only one I know is this.

at the start screen with the big bold letters FIGHTING FORCE 2 you can access a cheat menu with unlimited ammo invincibility but note that your own grenades do not carry infinite ammo because they are not really a weapon just explosives and the game cannot be saved when cheats are active it also gives you a level select L1+L2+R1+TRI+X+LEFT the start screen will disappear and select new game to view the mission select choose any one and you will be invincible but the trouble is it doesn't make you invincible against grenades and flamethrowers and stuff but you can't get hit by guns and turrets or anything that uses bullets.
Send in by LANSDOWNE49

Defeating the steel worker - When facing the steel worker at end of level 1, do not let him hit you. Hit him a dozen times and he should fall down and disappear. 

Level Select - At the main title screen, press the following - L2+R2+Square+Circle+Up
Start a new game, and you'll be taken to a Level Select Option, highlight a level and press X.

Build up Rage Meter with soda - Smash any pop machine untill cans fall out, press X while standing over one to drink from one. It will build up your Rage Meter. 

Capitalize on the stupid AI - In any level where there are desks that you can climb/jump onto and your enemies are not armed with any type of gun that they can shoot you with this trick will work . It's simple, if you are iin a room that meet those conditions just climb onto a desk. Your enemies will stand still, allowing you to take them down with YOUR guns. 

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