Get to the part where DP Brunton tells you that you should be close to Sadono's plane, and Fisher replies, "Really?". Look to your left. You should see a fence. Climb over this fence to find a drain pipe. Climb up the drain pipe and shimmy along the edge. Pull yourself up onto the ledge above. Enter the door and go to the right. You should find a switch. Hit the switch to turn the lights off. You can now dispose of the two soldiers guarding the plane. An alternate way is to get up onto the previously described ledge and shoot a Div Cam in front of both the guards. Press Y to knock both of them out.

After locating the first prime target, and just after you get the PDA information, use your optic cable to see through the door almost directly in front of you. You will see the room of hostages that you had to pass by unseen. Go into the room, stay low, then knock out the guard. Pick him up, then take him to the room directly in front. Shoot out the lights and put the body on the side of the bed. Double back then take out the guard left on the second floor on the balcony behind the door you started out by. Shoot out the overhang light above the stairwell, then the light in the stairwell hallway. Take out the guards one by one downstairs. Put them in the small room in the corner. This will take you to the next checkpoint, after you walk though the small hallway.

Whenever in a mission where several enemies are close by and there is plenty of light, it will be much harder to get past this area. Try shooting out any lights so it is easier to get out of any, 'severe' situations.

When you are in Miami (last mission) and you have just travelled across the lifts to get into the room with several balconies, you will need to get to the container. There many guards who are lethal and there are several civilians. Take out all of the lights with your pistol and make your way to the ladder ahead of you. Right above you is the container that holds pox. It will be much easier to reach now if you use your Sticky cameras. Shoot several close to the guards and then gas them while you are close to your objective.

When in Miami and you are near the pox container, there will be many civilians and guards. To know where all of your enemies are, use thermal vision so you can see the not so clear enemies on the balcony.

When you complete the game under the normal or hard difficulty setting, when you go back into the game make sure you go over towards the level select instead of checkpoints. You could lose your data and have to do it over again if the wrong choice is made.

To whistle, press Black. This will usually make a guard approach the sound. Note: Hide in a dark area and whistle, then jump the guard when he stops.

When using a Ring Airfoil, if you shoot someone in the head it will knock them out. Make sure you hide the body well. If a guard finds it, they will wake them up.

In order to find mines in the camp mission, turn on the thermal vision.

Before passing by a motion detector, pick up the body of a dead or unconscious guard. Then, proceed to walk past the motion detector. The motion detector should not go off, due to it seeing the guard on your shoulders, thus making you invisible to it.

When you are at a point that you can only use non-lethal attacks, make sure that you have the SC-20K and at least one Sticky Cam. Instead of waiting to sneak up on a person, shoot them in the head with the Sticky-Cam. This knocks them out without using "lethal methods". Aiming high is the key to knocking the person out because the Sticky Cams have a short range. After the attack you can pick your cam up and use it again.

To move quieter, crouch down and walk slower. This will make your steps softer, and keep you undetected to a limit.

When you have reached the airport car park in the back of the truck, kill the two guards and the dog. Then, face the truck again and turn left. On the left hand wall should be a door. Open it, and inside are some Sticky Shockers, Ring Airofoils, Sticky Cameras and a Med Kit.

Click the Right Analog-stick to zoom in the sniper scope, then press L to hold your breath. You should be able to get a good shot while Sam remains still.

To aim better with the pistol, press X to pull it out. The crosshair should appear normal. Then, press Up on the D-pad and the crosshair should become a laser sight. This makes it very easy to aim, since the laser sight is smaller and thinner than the normal crosshair. This allows fast kills and head shots. Note: If you are in dark corners and have the laser sight on, the enemies will notice and attack you.

After killing off all of Sadono's guards, lure him into a dark corner then shoot him with a Ring Airfoil. Then, run up behind him and grab him. You can now force him to use the retinal scanner and complete the mission.

In the intermission sequence where you see two ShadowNets neutralize the ND133, when Lambert picks up his coffee cup, you can see it has the Ubisoft logo.

In the Jerusalem mission, get to the part where you are following Dahlia Tal and can go up onto the roof and through an apartment to avoid being seen in the open area while she continues on. When you go through the apartment, you must sneak past two Israeli men watching television. If you zoom in on the television, you can see that it continuously scrolls a message in French from the development team thanking two people for their help with the game.

On the first half of the Jerusalem level, there is a book store directly behind an alley with a swinging lamp. Next to it is another smaller alley with a swinging lamp. If you look inside the large window you can see many different picture references to The Punisher, Ubi Soft's XIII, an anime, and a picture of the infamous "Sniper Kitty" among many other things. Use the binoculars to get a much better look.

In mission 3 (The Train With Soth), in the car with the cabins, go into the first cabin (with the open door). On the table there will be a comic book of XIII.

On the mission when you are on the train, look in the second car where the guard is located. Knock him out then go behind the fenced door. Look down you will see a magazine featuring Prince Of Persia.