Feature list from the 3.0 OBT

- Pick up loot and examine corpses (with old voice acting).
- Know how to use ladders.
- Throw grenades (planned in 2004).
- Use bolts at anomalies.
- Go around anomalies.
- Treat themselves.
- Changed algorithms of behavior in combat and calm state.
- Some NPCs with a higher rank may not agree to trade with the MC.
- Can change into better armor.
- Know how to trade with merchants.
- Can trade with each other.
- Can offer to trade in general chat if they have loot to sell.
- Can offer to trade with NPCs via PDA.
- Unknown stalkers eventually get nicknames.
- If you are surrounded by enemies, and nearby within the detection of contact PDA is a not hostile stalker, you can try to call this stalker for help through PDA dialog.
- New stalkers that appear in the zone have a random set of weapons and visuals.
- Send an SOS signal when wounded.
- Can get diseases and die from them.
- Merchants sleep at night and do not trade.

Gameplay:
- On the Master difficulty, you can only save where there is a roof over your head. (Anything that obstructs the sky works, including bushes)
- Most electronics depend on power sources.
An exoskeleton improves the mobility characteristics of the MC, but requires batteries.
- To learn the properties of artifacts, you need to have information in your PDA about it.
- Ability to collect mutant parts, if you have information in the PDA about it.
- Food spoils over time.
- The ability to remove the stalker's stash with his PDA.
- Physics and effects when underwater.
- Stashes on locations from each start of the game appear randomly.
- Food saturation depends on its state.
- Artifacts have random weight and price.
- And other stuff...

Other additions from the Design docs:
- Bulletin boards at merchants.
- Science Groups.
- Devices and suits with unique properties.
- Anomaly "Dead Zone" in which does not work equipment and electronics.
- Emission with respawning artifacts, anomalies and other chips from the design documents.
- Capsule R1 for storing radioactive artifacts.
- Artifact properties and capabilities from the design documents.
- Diseases
- Psi-weapons.
- Artifacts and anomalies.
- Ability to make fire and cook food.
- Thirst and fatigue (affects the mobility of the GG).
- Food and weapons found in the zone can be contaminated with radiation.
- Gravi artifact replaced by gravi-glove from the old concept art.
- Anomaly Discharger.
- And other things...

Locations:
- Restored two locations from the design documents (Rat Dungeons and Level12).
- Remodeled the children to match the OL builds
- Some locations were supplemented according to the literary plot and design documents.
- Added additional global lighting on static (hemi and sun sources).
- Geometry bug fixes.
- Connection of some locations.
- Supplemented the neighborhood of the location Pripyat.

Render:
- High-quality statics lightmaps without compression, with the ability to optionally disable them in options for weak graphics cards.
- Fixed din. shadows on static, improved shadow resolution and so on.
- Enabled fog calculation for children located at a great distance.
- Support HQ geometry.
- Wallmarks on dynamic objects appear in 99% of cases.

Restored (other):
- Minigun class from 1114.
- Additional HUD inertia as in 14xx.
- Restored old, more detailed calculation of all physics in the game (increased calculation accuracy, smoother simulation of physics as in demo builds).
- Restored the old NPC ragdoll (as in 14xx-18xx).
- Restored the HUD of items. Were in the builds up to 18xx (food, devices, etc.).
- Binoculars idle sounds, as in build 1154.
- Physical impulse on the MC from anomalies and mutants.
- Restored random voiceover when a NPC is in a calm state.
- Restored the sound of friendly fire between stalkers.
- Restored the sound of rapid breathing in combat in the NPC.
- Redesigned engine AI combat (similar to builds 18hx-19hx). Stalkers in combat are more mobile and active.
- The old look and functionality of the PDA.
- An artifact can appear from the death of a mutant in an anomaly.
- Changing the visuals of the hands of hermetic suits.
- Fog of War.
- The voicing of trade with stalkers.
- Ability to break vodka bottles.
- Limit on the volume of inventory and crates.
- Detectors react to artifacts as in 14xx.
- Handheld flashlight.
- Scattering static shadows from the sun on p1
- Panoramas of locations as in builds 11xx-14xx
- Flashlights don't go out when an npc dies.
- Zoom minimap on the keys - +
- Telekinetic monsters can throw corpses
- Illumination of the name of the stalker when pressing the action key
- Full-fledged communication via PDA
- Old sound of GG landing (if you have a suit)
- Stalker biographies
- Completely restored the old inventory (flashlight on the belt, grenade slot, 3d static, description of information about the GG)
- Mutants and npcs fly away from the impact of the car as in 1935

Offline A-life:
- Each new stalker appearing in the zone has his own global goal of being in the zone, and is engaged in its realization in real time.
- Move (travel through the zone) in all locations in real time.
- Fight.
- Collect artifacts, loot, hunt for information.
- Trade between themselves and merchants.
- Can die in anomalies.
- Send messages to the network about various events that have occurred.

Weapons:
- Double-barrelled guns can be fired together with a separate key.
- RGO explodes when in contact with geometry.
- Old tracer look + fixes.
- Additional alternate animation for bolt (was in old OL model).
- Old ricochet calculation.
- Restored barrel wedge animation.
- Fixed some engine bugs of the original engine.
- Gravi gun now shoots bolts.
- Edits to the position of the HUD for OL style.
- Geometry edits, and model replacements for some samples.

Transportation:
- Requires battery, gasoline.
- Appears with random col. fuel, battery charge.
- Old physics behavior.
- New hands on the steering wheel.
- Ability to push a stuck vehicle on the key TAB.
- Edit bugs.

Mutants:
- Controller can attempt to control the MC.
- Restored mutants from concept art (pseudohuman, posthuman, concept burer and bloodsucker, sentient swamp, phantasm)
- Restored jumping in dogs, controller, pseudo-giant.
- Monsters with jumping ability are able to jump over physical objects.
- Restored original engine psi-strike in pseudo-dog.
- Restored animations of panic, aggression, animations when the mutant heard a strange sound.
- Restored silent sneaking at the controller and the old psi attack (as in build 1935).
- Controller's wounded state
- Chimera regeneration
- Some mutants are afraid of campfires.

Optimization:
- Automatically adjusted simulation mutant population numbers.
- Added sectors and portals to locations for better performance.
- Some chips from previous versions are implemented through the engine, which gives a performance boost over scripted counterparts.
- Light sources are turned off at a great distance from the camera.
- Disabled loading of textures into RAM, which significantly reduced its consumption.
- For very old video cards it was added compression option for new (heavy) lightmaps. Significantly reduces video memory consumption. Enable only for video cards with <= 512 mb memory.
- Other engine optimizations.

Other edits/fixes:
- Added backpack ammo repacker.
- Artifact merger does not work instantly.
- No dust under the feet of NPCs and monster paws during rain
- Quicksave Counter.
- Fixed zero ammo packs (now the amount is random for each pack).
- Added autosaves.
- After getting a certain ending, it is possible to continue the game in freeplay mode (creates a save start_freeplay_olr in the saves folder).