How to stay healthy and happy in the Zone.

G.A.M.M.A. uses a modified version of the Body Health System, which drastically changes the way healing and damage is handled. With this mod, being damaged in a certain body part damages that limb's overall health. Increasing limb damage leads to different effects, and is separate from the player's overall health. Healing now requires two components: temporary "first aid" healing, and permanent "post-heal" health.

All of this information is available on the mod's page.

Right now, G.A.M.M.A. models damage to the head, torso, left and right arms, and left and right legs.

Low head health produces disorienting visual effects: wobbling screens, fading in and out of blackness, and blurry vision. No head health leads to death.

Low torso health reduces your carry capacity. No torso health leads to death.

Low leg health reduces your movement speed, and trying to sprint will cause general health damage. No leg health in one or both leg stops you from being able to sprint.

Low arm health causes your aim to wobble. No arm health in one arm stops you being able to effectively use two-handed weapons such as most guns, though you can still use pistols and knives. No arm health in both arms stops you from being able to hold a weapon, causing you to drop your equipped weapon.

General body health can be recovered by using certain healing items such as first-aid kits. Read an item's tooltips or go into their details page to see exactly how much they heal, at what rate. Standing next to lit campfires also slowly regenerates general body health.

Limb damage must be tended to with yellow first-aid healing items to grant "temporary" health, which is then "fixed" with a post-heal item into regular hitpoints. This "temporary health" will fade over time, dropping back down to your maximum "post-heal" (white) health.

Remember, the sequence of events is: use a limb first-aid item > use an appropriate post-heal item. Many post-heal items take a long time to apply, or produce visual effects simulating dizzyness. Therefore it is generally best to wait until you are out of combat before using them.

Not all post-heal items work on all body parts, so read the tooltip carefully before use.

Alternatively, limbs can be healed by paying medics to completely heal you, or by going to sleep. Sleeping does not restore general health, only limb health.

Bullets and slashing mutant attacks – basically, attacks that do Rupture damage – can cause bleeding damage. If you're bleeding, the edges of your screen will be red and pulsing.

Stop bleeding by applying healing items that reduce bleeding (duh). Early-game, this will probably be a bandage or a tourniquet. Later on, tourniquets are still useful since they apply instantly, but higher-tier medkits also slow bleeding, as do certain meds.

If bleeding is being reduced, you should see an icon in your HUD.

You must also manage your hunger and thirst while you're in the Zone. Similar to other survival games, you must eat and drink appropriate items. Running low on thirst or hunger gradually damages you over time, and can result in death if you don't deal with the problem.

Simply "use" consumable food or water items to fill up your bar. Remember that different foods and drinks will restore different amounts of your meters, and you may require more than one food item to completely fill up. Eating large, high-calorie foods also tends to increase your tiredness, so eating a big meal before you want to sleep can be a good idea.

Food and drink produced outside of the Zone, such as canned food, MREs and bottled water, will not give you radiation when consuming them. Zone-produced food and drink, such as cooked mutant meat, will give some very slight radiation when eaten. Usually, this can be countered by drinking clean water, smoking cigarettes, or drinking vodka.

Players slowly get tired over the course of the day. Many types of medicine also increase tiredness, so using medical items in quick succession will likely make you sleepy. Large meals and ingesting alcohol also make you more tired.

Being sleepy is not necessarily a bad thing, especially early on before you have good ways to navigate night time. By default, if your stalker is not sleepy enough they cannot go to sleep. Being very tired increases the chances that you oversleep, and being only lightly tired increases the chances that you wake up earlier than intended.

Players can use sleeping pills to increase their tiredness if they want to sleep immediately. To fight off tiredness, players can use glucose shots, caffeine pills, coffee or energy drinks to stay awake. Many of these stimulants also give buffs to stamina regen and carry weight.

Radiation works a little differently than hunger, thirst or tiredness. When standing in radiation patches, or if holding onto unshielded artifacts, players will slowly accumulate radiation. As radiation rises, you will start to lose health. External radiation in G.A.M.M.A. is more potent than in Anomaly, so make sure you have adequate radiation resistance especially before venturing to the more-irradiated north of the map.

Q: How do I know I'm in a radiation field?
There will be a film-grain-like effect in the background (most visible against the sky), you'll hear a crackling sound, you'll see a round radiation symbol icon in your HUD, and you should see the radiation bar in Body HUD slowly start to rise.

Radiation can be cured by using anti-radiation drugs, drinking vodka and purified water, sparkling water or beard tea, or by smoking cigarettes. Anti-radiation drugs tend to quickly cure many rads but incurs heavy hunger and tiredness penalties. Vodka and cigarettes work more slowly but the penalties are less steep than taking anti-rad drugs.

Vodka and cigarettes being able to slowly cure radiation poisoning in the base S.T.A.L.K.E.R. games is probably a reference to the old Soviet folk belief that vodka or grain alcohol can cure or combat radiation poisoning.