On missions such as Kalinatek, you may find that ammunition and Medikits are scarce. You may notice that it takes 2-6 shots with a weapon to kill an enemy. If you aim for the head from a secluded location about 10-30 feet away, you will almost indefinitely kill your target without being noticed, that is, until the body is found. To keep your Medikit supply up, save them until your health is about 40% or less. That way, it would be a lifesaver rather than a refill. Hope these helped! Thanks :3
If you are going to try and lockpick a door, don't rotate it slowly as the game suggests. Instead, press the Analog-stick in one of the four diagonal corners, until you hear the click. Doing this is much faster.
On the level Kalinatek right when you start out turn to your left and run to the white van. wait for a guard to come out. DO NOT SHOOT HIM!!! If you shoot him the guard that comes in behind him will shoot you. (remember they have automatics)So wait for the two to start talking then they both will start patroling and one will walk behind a pole. Zoom in and shoot him in the head. Now get behind the van and wait for him to run over infront of you. Press L3 for fully automatic and blast him. The rest of the mission it doesn't matter how you kill the bad guys but just save ammo you really really need it!
If you're about to enter a room that you've never been in before, let the camera look in there before you go in the room. That way, you'll get a heads up before you run into an enemy or a camera.
If you find you are running low, use the sticky cams as non-lethal ammo.
These are especially good on levels where killing is forbidden. Also you can pick them up and re-use them.
In Some part of the games you won't be given a code to a keypad doors. So you can use the thermal goggles as a way to open them. Turn on your thermal goggles and get to a keypad and press the keys that appear from lightest to dark in order.
If your on from a good place to jump, and theres a enimy below you, you can jump on them and kill em.
The Keypad Door: 28469
Mission 1, Police Station
Blaustein's Balcony Door: 091772
Mission 2, Defense Ministry
No Keypad Doors
Mission 3, Oil Refinery
No Keypad Doors
Mission 4, CIA HQ
Technical Services Room: 7687
Battery Generator Backup Room: 110598
Storage Room: 2977
Main Server Room: 2019
Weapons Testing Department: 110700
West Entrance to Information Retrieval: 0614
Mission 5, Kalinatek
Security Door: 97531
Archives Department: 33575
Back Door on Third Floor: 1250
Mission 6, Nuclear Power Plant
Cooling Rod Control Room: 560627
Door to Maintenance Shaft: 151822
Maintenance Shaft: 795021
To do a split jump, press triangle three times in a corridor that is about as wide as Sam is tall.