While playing the game, hold LB + RB and quickly press Right(2x), Down, Up, Left(2x) to unlock all weapons.
When flying a helicopter in Multiplayer mode, if you start to get laser targeted (not GTAM), fly as fast as possible, and at the same time get as low to the ground as you possible. If done correctly, the missile will hit the ground and miss you most of the time.
Unlock the Frag Grenade weapon challenge, then successfully complete all rounds and kill all enemies through round ten. If every enemy is killed, you will go into round eleven. In this round, the soldiers move and create the shape of first an “E”, then an “A” as a reference to EA Games.
When doing the Hotswap Challenge, it is easier if you move towards the marker to make more “Hotswaps” available. By doing this, you will not lose 1,000 points.
RPG Rocket Challenge
When doing the RPG Rocket Challenge, the further you are away when you blow a vehicle up, the more points you get. An easy way to get points is to take a vehicle’s shield down at close range, hotswap to a further away RPG man, then finish the vehicle off.
Get two helicopters easily in Air Traffic Control level
At the beginning of the Air Traffic Control level, you will start out as a sniper. Directly behind you will be a chopper. Turn around as soon as the level begins to get a good shot. Shoot the pilot and the chopper will fall a short distance directly in front of you. Make sure you hit the pilot, and not the chopper or it will explode. Note: It may require a few attempts to hit the pilot. You can then get in and shoot out the turrets with the chopper. When the jeeps come by, hotswap to one and go directly past the turrets and into the helicopter inside the heliport. You will not have acquired two helicopters, making this level very easy.