There’s an abandoned water tower on the side that you can climb and use as a perfect vantage point. If not, you can also use the cliff on the opposite side of the outpost. The rooftops of the three buildings will each have a lookout. Take them out if they’re within range of your bow or suppressed weapon.
A majority of enemies will be in and around the main building. Securing the main building allows you to easily sneak behind the other guards and puts the other two lookouts in range. The back of that building is lightly guarded so you can easily sneak and climb to the roof using the ladder there. The opening on the roof will allow you to peek inside as well to snipe other enemies.
In higher difficulties, you’ll encounter at least one enforcer in the walkway of the main building and one as a lookout. If you can snipe them and kill them with one shot, they’ll be pretty vulnerable once you identify their locations and patterns. From there, it will pretty easy to sweep the remaining enemies since they’re pretty scattered.
Having a bow powerful enough to one-shot enforcers will make undetected liberation attempts for the highest tier outposts a lot manageable. Just get either the elite compound or recurve bow and upgrade them several times until their base damage is around 1800 or 1920. One-shot kills against these tough enemies are very important since they can easily call for reinforcements if they’re injured and can easily detect you even when crouching or in cover, blowing your cover before you can even make your move. Thes sample videos below will feature strategies surrounding this weapon.
You can refer to the sample videos below on how to achieve undetected or at least "No Alarms" liberation. Due to some random factors out of your control, like random animal attacks or friendly NPCs wandering near the outpost and triggering a response from enemies inside, you should adjust your strategy accordingly.
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