Right, the energylink overload is an instant silent kill against unshielded targets (despite the stars like a knockout icon on the nameplate, it is a kill), and if you do it out of sight range of others, you can proceed to still be visible to guards without them immediately opening fire. Keep in mind though if they scan you they will discover you killed and open fire, but outside of the range where they tell you to stop so they can scan you, they won't aggro. Just stay away from the body for a while once someone finds it, though, as they'll be cautious, and I'm not sure if or if not they'll aggro you on sight when they're cautious around a body. After a while they'll lose their caution and it'll be safe to be in their line of sight again.This![]()
You can still use stealth to a limited degree if you've aggroed a base, you simply have to stay out of everyone's line of sight and don't make much noise. Crouching and moving silences your footsteps. Moving without crouching while the base is hostile makes NPCs investigate the sound, even if it's in another room out of their line of sight.
Keep in mind that if you really need the guard type NPCs to be somewhere else, as long as the alarm systems are on, there are certain actions you can take that will pull most of the guards to a distraction. Things like opening sample containment units, shutting down the power center, etc, will draw guards to the location at which point they'll undo whatever you did and look around for a while, giving you the chance to do other things. Now, I may be wrong about this, but I believe uploading things like spyware to a data port, despite causing monitors to start showing alarm states, don't actually alarm an entire settlement, but if an NPC sees the data port during this, they will investigate. I learned this from two missions: One where I had to upload spyware to a power plant data link that was behind a console the NPC in there couldn't see, and a pillar I kept sneaking around to not get seen either. Then I had a tourist site uploading mission where I uploaded spyware to a data port in the bar area, then hid around a corner, after which a bartender noticed something wrong with the data port and eventually found me, turning hostile.