Timber is the best companion for stealthily clearing outposts. He can instantly spot enemies and alarms you haven’t tagged yet even behind walls. This significantly lowers the chance of you getting spotted accidentally and ruin your undetected run. His other skills include being able to tag materials in the nearby areas as well, making him even more ideal for stealth approach. When maxed out, Timber can even pin and take down elite enemies.
The Judge is a New Edener that is a primarily stealth-focused companion. He’s also equipped with a bow, making him ideal for these attempts.
Finally, Nana is another good option for stealth liberations. She’s equipped with a suppressed sniper rifle and pistol by default. She has great range and can take down targets with headshots from a great distance.
Make sure to upgrade the Training Camp facility to improve your companion’s health and damage and allow them to take on higher-ranked enemies.
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