Survival needs

Your body keeps its own books, and it doesn't forgive for long. Watch the HUD, and open Medical with F2 whenever you're unsure how you are.

Food and water

A full stomach lasts a bit over an hour of play, and a full canteen about three quarters of an hour. Sprinting burns both twice as fast. Once either runs out you start losing health, so eat and drink before you have to.

• Dirty water from rivers, ponds and faucets makes you ill. Boil it at a fire, or use purification tablets, a filter straw or a solar still.
• Raw meat and fish need cooking. Raw, your body gets little out of them and they can make you ill; spoiled or rotten food can make you sick and adds to your infection. See Fires and cooking.
• Your stomach holds about a quart and a half comfortably. Eat past that and you're stuffed and short of breath; keep going and you'll be sick, losing most of what you ate. Food leaves your stomach over about ten minutes and a drink over two or three, so pace your meals. The HUD shows Full, Stuffed or Overfull beside your food when it matters. Nothing counts until your gut absorbs it, so your gauges rise over a few minutes after you eat or drink. See Your body.
• Food spoils over time. Coolers, ice and a powered fridge slow it down, and cans and dry goods keep longest.
• Hunting and fishing are the long-term answer. See Hunting and fishing.

Rest and sleep

You get tired the longer you stay awake, faster at night and when you run and fight. A normal session won't get you there; a long raid or a night out will. Past about twenty hours awake your first shot comes a beat late, your breath comes back slower and the edges of your sight close in; worse than that and you nod off on your feet and start hearing things. Sleep in a bed, a bedroll, a car or on the ground: the night goes by in a couple of minutes for you while the world carries on. See Sleep and exhaustion.

Temperature

The weather is regional, and the air, the wind and the water all pull heat out of you. Cold makes you shiver, which burns food, and hypothermia takes your sprint and then your health. Heat drains water and can put you on the ground with heat stroke.

In the heat you sweat, and the sweat soaking your shirt is what keeps you cool as it dries. That works far better in the dry desert than in sticky coastal air, and it stops when you run out of water to sweat. Hard work in the sun, heavy clothes or armor and an empty canteen push you into heat exhaustion: a racing heart, stamina that won't come back, a pounding headache. Push on and it becomes heatstroke: the world swims and you collapse.

• Get indoors, into a running vehicle, under a camp shelter or next to a fire.
• Wear clothing that suits the region. The north is much colder than the desert, and the mountain can snow while the coast rains.
• Gloves and dry boots matter in a hard frost. Bare hands or wet feet in a bitter wind can give you frostbite.
• In the heat, find shade, drink, and don't sprint at noon.
• To cool down fast, right-click a bottle or canteen of water and choose Pour it over yourself, or wade into water. Wet clothes cool you in the heat, but they'll chill you once the sun goes down.
• Being cold and wet for a long time can give you a cold. See Dirty water, hygiene and sickness.

Wet clothes

Rain, snow, wading and swimming soak you, and soaked clothes keep only about half their warmth. Wind makes it worse. You dry off slowly with warmth and wind, and quickly next to a fire. Cold water is dangerous: a swim in the Pacific can bring on hypothermia in about ten minutes.