You’ll first encounter a screamer during the Story Mission Drinking Himself to Death. If a Screamer spots you, she will let out a scream that will spawn five swarmers Out of Nowhere. If there are nearby freakers, it will also get their attention. If you also drive near a screamer and you’re really close when she screams, Deacon will get disoriented and nauseated, making driving harder.
Once she summons her freakers, she will keep distance and even attempt to escape. Screamers aren’t really tough targets so a few direct hits can take them out. A well-placed headshot can also take her out instantly. Since they're also kind of jittery, use focus to make your shots more accurate.
These special freakers usually travel alone and are always in the lookout so it’s hard to sneak behind them unless you have a lot of cover. The best way to Defeat them without dealing with the summoned freakers is to spot a Screamer early and kill her with a head shot.
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