• v0.51 - July 26, 2016 - Fixed a typo in the permanently-alarmed guards mini-section.
  
• v0.5 - Jan 7, 2016 - Replaced the turning an enemy in place screenshot with one that's closer up.
  
• v0.4 - Dec 30, 2015 - Added a screenshot demonstrating pulling a particular enemy from a group. Added a mini-section about permanently-alarmed guards.
  
• v0.3 - Dec 28, 2015 - Added a screenshot demonstrating turning an enemy in place.
  
• v0.2 - Dec 27, 2015 - Added a screenshot demonstrating the first exploit.
  
• v0.1 - Dec 24, 2015 - Text only version. I will see if I can add some appropriate screenshots later.

I'm sure this has happened to some of you before. You're trying to use a distraction to attract a guard to a particular location, but he doesn't even bother to check the distraction. If this is happening to you, you fell prey to this glitch. Before discussing how to set things back to normal, let's look at how the glitch works.

For the purposes of this guide, let's assume every guard has an "alarmed flag" that determines whether he is the one chosen to check a distraction or not. As such, only one flag can be enabled at a time. When guards first become alarmed, the game first chooses whose flag to enable based on who is closest to the source of the disturbance (whether it is the source of impact for a noise disturbance or your location for a visual disturbance). Once a guard is chosen, the guard heads over to the source of the disturbance, and the flag is disabled once the guard calms down (i.e. the arrow representing the guard on the radar is no longer yellow).

Triggering the glitch involves a bug with how loading works. In fact, when you load your game, the state of the alarmed flag is not reset. As a result, loading while a guard is in the middle of searching will cause only that guard to check disturbances while all other guards will give up almost immediately.

Most of the time, the glitch is triggered by accident, so it is very important to know how to undo the effects of the glitch whenever it gets in your way. Currently, there are 3 known ways to end the glitch:

1. Let the affected guard finish his search - Simply put the guard with the enabled flag into the alarmed state again and wait for him to relax before loading your game. This method is useful when you are not ready to take out the guard yet.
   
   
2. Dispatch the affected guard - If you are ready to take out the guard, though, then simply eliminating him will work as well. The method used to take out the guard does not matter.
   
   
3. Turn any guard hostile - Sometimes, you have no clue who is causing the glitch. In such a case, the fastest way to end the glitch is to turn any guard hostile. Some methods include letting a guard see you for too long, bumping into a guard, or using blind cover fire.

While the glitch is generally seen as a nuisance, it is also an incredibly powerful tool for stealth gameplay. In particular, it can turn incredibly difficult double takedown setups into a trivial matter. Here are the currently known ways to make use of the glitch:

• Attract a particular guard to a particular location - Perhaps the most obvious usage of the glitch is to attract whoever you want to any accessible location, regardless of whoever else may be closer. For instance, shoot using a silenced pistol near an unaffected guard in order to bring the two together for a double takedown setup.
  
  
  
  
• Prevent a guard from leaving his post - Sometimes, making noise from, say, falling is unavoidable, but this trick will make such distractions inconsequential (as long as you are not seen). Simply use the glitch on some other guard, and everyone else will leave you alone. One example is the first room of the Sarif Manufacturing Plant mission, where falling down the levels of shelving normally attracts the attention of the PF member searching the crate in the narrow corridor.
  
  
• Make a guard turn around - By creating a distraction behind an unaffected guard who is blocked from his patrol route, the guard will simply turn in place. This is obviously useful for stealth situations, but it is most useful for setting up Buffer Zone Takedowns[deusex.wikia.com]. Normally, getting such a guard to turn around will also cause him to move away from the buffer zone, so this trick can make setting up these takedowns much less frustrating. Note: This trick does not work on all guards, particularly ones who forcefully teleport back to their patrol route if blocked.
  
  
  
  
• Pull a guard away from a large group - Groups of 3 or more can make setting up double takedowns difficult. While it usually works to pull away any guard, this trick can be useful if one of the guards is special or has different behavior from the others.
  
  

A note about permanently alarmed guards

Believe it or not, the glitch will still work on guards like the ones in the AGP ambush or Picus Web. However, it does not work exactly the same. Since the guards essentially act like they are on high alert, an unaffected guard will still look at a disturbance for a while before returning to normal. Bringing two guards together won't work either, because the unaffected guard will typically move away from the disturbance and let his buddy check it out. As such, the glitch is not as useful against these guards, and you are better off using visual distractions and patrol re-routing/blocking in order to setup double takedowns.

If you have any questions about the glitch or the guide, or you would like to contribute screenshots/videos demonstrating the gltich, feel free to leave a comment.