Payday 2: A guide to stealth

This is the first part of a guide that I am doing in order to explain the stealth in payday 2.
This part will include the in-game features that payday 2 offers in every heist, like cameras, guards and other stuff.
Comment down if I have missed something
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This is not the whole guide, in the future I will post the stuff I have not talekd about.

Firstable, I am going to talk about the in-game features that a player MUST understand and "dominate" in order to achieve a succesful stealth.
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THE CASING MODE:
Casing mode is a gameplay mechanic available in some heists, where you can explore the map of the contract and interact with the environment; For Example you can mark the security guards and pick up keycards (If you have the abilities).
In cashing mode, you don't have your mask, so you won't be able to shoot anyone, crouch, put drills, etc.... But have in mind that your detection rate is very low while you are in this mode,
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STEALTH:
While doing stealth, you must have in mind the following features:
---- As long as you are not detected by anyone, any hit will be fatal (can be a shot or a melee attack), but you must be careful when you kill a guard, DON'T KILL HIM IF OTHER GUARD/ENEMY CAN DETECT YOU, because their health will increase significantly, and the might alert other people or shoot you.
---- When you kill a guard, you MUST ANSWER A PAGER, and you can only answer 4 pagers, so be careful with the amount of guards you need to kill.
TIPS:
* If a guard gets alerted, you can attemp to intimitade him (shouting at him, if you have the DOMINATOR skill), he might get down onto his knees and cuff himself, you can kill him.
*ALWAYS PICK UP THE BODY OF THE GUARDS IF YOU DON'T KILL HIM IN A SAFE PLACE (like a corredor or a room).
*If a guard gets alerted, the guard can approach the player and handcuff him, you can take advantage of this if killing the guard compromises the mission (Been seen by other guards, cameras or civilians).
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Cameras:
The player can shoot and deactivate cameras (Overkill and higher difficulties might have a different type of camera, which can't be shooten).
TIPS:
*A camera that was shot can alert guards, so I DON'T RECOMMEND TO SHOOT THEM IF GUARDS CAN PASS NEAR THEM)
*Some heists have a security room, where there is a guard (or a civilian, in some heists) "watching" the cameras, IF YOU ENTER TO THE ROOM (you can use ECMS or a keycard) AND KILL THE GUARD, THE CAMERAS WILL BE DEACTIVATED.
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CIVILIANS and CABLE TIES:
Cable ties are used to take civilians hostage. When civilians are ordered to lie down, a player can use cable ties to tie them up. This stops the hostages from running away, possibly alarming the police.
TIPS:
*If you tie up a special civilian (like managers), they can drop an item, like keycards
*You can move hostages to a safer place, in order to avoid getting detected.

This is the first Article that I have done about payday 2, in the future I will post more about the game.
Thanks