Code - Result:

LB, LB, RB, X, RB, Y - Put your life at 100%
RB, RB, LB, X, LB, Y - Unlimited Ammo
X, X, Y, RB, Y, LB - Team Invincible
Y, Y, X, RB, X, LB - Scott Mitchell Invincible
Y, RB, Y, RB, X - All Levels

Sluggish controls  -  If you are carrying a large automatic weapon, the controls will feel sluggish because of the weight of the gun. However, if you switch to a hand held gun, the controls will be more responsive.

Xbox Live music help  -  Keeping the music on is recommended, as the tempo picks up when you are approaching the enemy. Conversely the music slows back down when you are at a safe distance.

GRAW: Fly  -  Go by the last seen spot of the V.I.P. Dive out in front of the car and switch to assault. Call the team to regroup and go forward while lying down. You will fly a few inches above the ground.

Achievements  -  Complete the following to unlock GRAW's Achievements:

Perfect chapter 1 (Multiplayer)  -  Complete all primary and secondary objectives in chapter 1

Locate the Football (hard)  -  Take the Football back from Carlos Ontiveros

Capture Ontiveros (hard)  -  Capture General Ontiveros alive

Reach the Football (normal)  -  Reach the Football's location

Clear the way (normal)  -  Clear access to rebel HQ

Capture Ontiveros (normal)  -  Capture General Ontiveros alive

Locate the Football (normal)  -  Take the Football back from Carlos Ontiveros

Secure Ballantine (hard)  -  Secure the US president

Escort Ruiz-Pena (hard)  -  Escort the Mexican president to US Embassy

Neutralize rebel outpost (hard)  -  Neutralize a rebel outpost blocking the highway

Eliminate defenses (hard)  -  Eliminate Chapultepek castle defenses

Secure US tanks (hard)  -  Take control of 50 US tanks stolen by rebels

Protect US president (hard)  -  Locate and protect US president

Reach the Football (hard)  -  Reach the Football's location

Clear the way (hard)  -  Clear access to rebel HQ

Protect US president (normal)  -  Locate and protect US president

Secure US tanks (normal)  -  Take control of 50 US tanks stolen by rebels

Eliminate defenses (normal)  -  Eliminate Chapultepek castle defenses

Neutralize rebel outpost (normal)  -  Neutralize a rebel outpost blocking the highway

Escort Ruiz-Pena (normal)  -  Escort the Mexican president to US Embassy

Secure Ballantine (normal)  -  Secure the US president

Reach Ramirez (hard)  -  Reach Captain Ramirez's position

Reach Ramirez (normal)  -  Reach Captain Ramirez's position

Team champion (Multiplayer)  -  Climb to the top of the team leaderboard

Solo champion (Multiplayer)  -  Climb to the top of the solo leaderboard

World Champion (Multiplayer)  -  Climb to the top of the universal leaderboard

Coop 1-4  -  Win missions in the cooperative campaign
Coop 1-3  -  Win missions in the cooperative campaign
Coop 1-2  -  Win missions in the cooperative campaign
Coop 1-1  -  Win missions in the cooperative campaign

Master of Ceremonies  -  Host at least 1000 matches

Committed (Multiplayer)  -  Play for 8 hours straight in multiplayer

Sniper (Multiplayer)  -  Get a career total of 500 head shots in multiplayer

Falcon (Multiplayer)  -  Shoot down 100 helicopters in multiplayer

Deadly (Multiplayer)  -  Get 4 kills in 4 seconds or less in multiplayer

Heavyweight (Multiplayer)  -  Get a total of 10,000 kills in multiplayer

Walls and barriers  -  You cannot hide behind walls or barriers in first person view unless you plan on staying at that location for awhile. Unlike third person view where you can just tap Y to automatically hide, you must hold [Y] in first person view to hide. Press [Up] to look over a barrier or to open fire. Press [Left] or [Right] (depending on how you are positioned) to look out.