Threats come from distinct sources, and each requires a different approach.
The Infected (Zombies): Avoid fighting groups. Use stealth by crouching, or trap them inside buildings by running through a door and shutting it behind you. If forced to fight, aim strictly for the head with a melee weapon or a suppressed firearm like the MK2.
The Environment: Rain ruins your insulation. Swap basic starting shirts for high-insulation clothing (like hunting gear) as soon as possible to keep your immune system strong.
Other Players (PvP): DayZ is famous for its tense player interactions. Most players operate on a “Kill on Sight” (KOS) mentality to protect their own loot. Assume every stranger is hostile until proven otherwise, and never loot a fallen body immediately without clearing the area first.
AI entities: Like predators (bears, wolves) or bots.