Cheat mode:
Enter the Goals/Notes/Images screen. Press L2, R2, L1, R1, Start, Start, Start to view another tab on this screen with the following options: God
Full Health
Full Energy
Full Ammo
Full Mods
All Skills
Full Credits
Tantalus
Annoyed people
In every level are small items that you can pick up. Find such an item and look for a friendly person (green target cursor). Throw and hit the person with the item to get random reactions. Do not try this on an enemy unless you want to get shot.
Slow reaction time
Standard (non-Boss) enemies you encounter have a slow reaction time when spotting you. The farther away you are from the enemy, the longer it will take for him to spot you. All enemies except for Bosses will say something such as "What was that noise?" or "Who's there?". If this happens, it does not mean that they know you are there -- they only think that you are there. If you hear en enemy say something similar to that, look for cover, because they will investigate. This trick will not help you if you are out in the open.
Killing Grays
There is trick to killing a Gray with a pistol or a low-tech weapon. Since the Grays are quick, you have to do this fast. Aim for the legs when using a pistol. Then, shoot them slightly above the torso, at about the neck area. They will die with one shot. Note: You need to do this with pistol advanced or trained. If you do this with it untrained, you will get killed easily.
With a combat knife or crowbar, find a medkit. Stand near the Gray and slice it only on the neck. When it needs just one more slice, slice it near the crotch. It will die very easily, and will be prevented from firing the Radiation Cannon. Use the medkit since you have been damaged by the radiation. It will heal about 25, depending on how long it took you to kill it, and how much damage you took. If it is over 45 or 50, find the nearest Medbot. Note: It is much easier to kill it with throwing knives by doing the same process. If you have lower than advanced, you will automatically die.
Killing robots
You can kill robots with just about any weapon, but it will take awhile when using a shotgun. With a normal unmodified clip, it will take over ten clips, and you will need God mode.
Blind enemies
Shoot the fire extinguishers that you see occasionally throughout the game to blind your enemies.
Easy money
When you are at the Lucky Money in Hong Kong, get Inside the club and go where the door girl is located. Kill her, then right click on her to get some credits.
Extra items
When you are low on items, go up behind a security guard and make sure there are no robots, other guards, or cameras around. Hit him with the crowbar. He should die instantly and have bullets, knockout ammo, explosives, and a few other items that are very useful.
Control credits
Press [Up] to roll the credits faster or press [Down] to slow them down.
Candy bar in training missions
When doing the training missions, you are taught how to climb ladders. In this room, there are two pipes on the left wall. Go to the far end of the room and look down the end of the pipe to find a candy bar.
Keep weapons in training missions
When you leave each area, throw your weapons down before the UNATCO Guard talks to you. You can then pick them up and use them in the next area. Note: The handgun and sniper rifle will lose all their ammuntion, but you can use the "Full Ammo" cheat to regain it.
Secret room in training missions
On the last room of the training missions, where you look at different holograms to learn about people, there is a brick sticking out on the left wall (about halfway down). Push this in, and the wall opposite will open. Go in to receive an interesting message from Jaime.
Secret area in alex's office
In Alex's Office, just past the desk in the middle of the room (on the right side), there are two hidden hatches in the floor. Go down one (they both lead to the same place) to find a scope weapon mod, credit chits, a lockpick, and some other items.
