For these Mercenaries 2 codes and cheats to work, please make sure you have the latest version (via Xbox 360 patch/PS3 update) of the sandbox shooter by playing the game on a console that’s connected to the internet. The PS2 & PC versions don’t need this for cheat codes to activate.
First enter the cheat codes mode:
While playing the game, press the Back/Select button to bring up your PDA. Type in: LB RB RB LB RB LB LB RB RB RB LB on Xbox 360 and L2 R2 R2 L2 R2 L2 L2 R2 R2 R2 L2 on PS3 (or simply go to the Factions menu on PS2). Close the PDA and re-open it like you did before. You will get a prompt. Then, without moving the cursor off the PMC on the map, type the following codes on the D-Pad.
PLEASE NOTE: Using cheats will prevent achievements from being earned on the save file you’re using.
Each cheat code is followed by its effect:
1. Up Up Up Down Down Down — Fill Fuel*.
2. Right Left Down Up Right Left Down Up — Give All Airstrikes (except Nuke)*.
3. Left Right Right Left Up Up Left Up — Give All Supplies*.
4. Up Down Left Right Right Left — Give All Vehicles (25 each)*.
5. Up Up Down Down Left Right Left Right — Give Nuke (25)*.
6. Up Down Left Right Left Left — Infinite Ammo*.
7. Up Down Left Down Right Right — Invincibility**.
8. Up Right Down Left Up — Unlock All Costumes*.
9. Up Left Down Right Up — Unlock Grapping Hook**.
* Can be done by either player, but only affects the player who entered the code.
** When executed by either player, activates for both players. If a client joins a game, they have access as well.
Thanks for Joseph for sending this in.