A fast paced multiplayer shooter that pits aliens against humans in a strategic and action-packed struggle for survival!
Recent Reviews:
Very Positive (79) - 92% of the 79 user reviews in the last 30 days are positive.
All Reviews:
Very Positive (6,086) - 85% of the 6,086 user reviews for this game are positive.
Release Date:
Oct 30, 2012

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Recent updates View all (169)

November 23

UWE Group Resurrection

This Steam Community group has been neglected. For eight years, we forgot it existed. Before this post, the last update was from Flayra in January 2010, offering Natural Selection 2 pre-orders! It's time to bring it back to life.

Back in 2010, Subnautica wasn't even a twinkle in anyone's eye. NS2 hadn't topped Steam on Halloween. People were using iPhone 3's. Windows 7 was only a few months old. This is a vintage Steam Community, and resurrecting it is an opportunity for reflection.

Since 2010, Unknown Worlds has been through a lot. We've navigated near-death financial valleys to the heady heights of #1 top-seller on Steam. Our team size has grown from around 10 to around 40. We've gotten a little older, a little wiser, and formed firm friendships as a team.

Through it all, the consistent force behind our survival and success has been you. You've hurled feedback on Twitter, debated design on Discord, reviewed roadmaps on Trello, shared trailers on YouTube, endured horrific Early Access bugs, delayed updates, awful frame rates, and so much more.

Your engagement with the development process is the critical secret sauce. Without all of you, our games would probably suck.

To everyone that has followed us since 2010, and before, and to everyone that is with us now, and to those thinking of joining us in future, thank you. We're pumped to keep making great games with you.

- Unknown Worlds

14 comments Read more

October 29

Update 325 - Anniversary

Update 325 includes balance adjustments, map refinements, bug fixes, gameplay tweaks, and new cosmetics to the Catalyst Pack. A long time veteran of NS2 development has rejoined the team, Fsfod is back and putting all his focus on improving and stabilizing LuaJIT. Fsfod was the original developer that implemented LuaJIT support for NS2. His efforts will ultimately yield a faster and more stable game.

The Machine Gun is getting some needed love this update. The Commander is no longer required to research it separately after upgrading to an Advanced Armory and we have lowered the cost of the Commander weapon drop as well. Additionally, with a lower overall weight and slight increase to the base damage, this is starting to feel like a better weapon choice to have in a group of Marines later in the round.

Sound is a critical component of NS2 gameplay. Hearing the clatter of claws on metal can mean the difference between life and death. Our resident audiophile Sweets has prepared an overhaul of audio cues, from footstep distances to Gorge Tunnel sounds over the last few patches and now has taken a peck at the Lerk glide and ambient sounds for additional player tracking.

Last update we introduced the Catalyst Pack, new Sandstorm skins for all Marine equipment, and Toxin skins for all Alien lifeforms. This update we are adding to that DLC, Catalyst now gives the Command Station and Hive the cosmetic DLC love they’ve always deserved. This update also includes cosmetic options for Alien Eggs and Harvesters as well as Marine Extractors.



*Proceeds from the sale of all NS2 DLC items, including this new Catalyst Pack, go towards funding the on-going and long-term development of NS2.

Since this is Halloween, we have added our first ever animated shoulder badge. This spooky new babbler badge will unlock after completing just five rounds of play that are at least five minutes long.


Check out the full changelog below to see all the goodies contained within.

Follow the NS2 development roadmap to see our plans for future updates.


  • Machine Gun tweaks
    • Now unlocks with the Advanced Armory
      • We felt that accessibility was an issue preventing the weapon from being seen in most games, with the research cost and research time not being justified by the stats.
    • Lowered weight to 0.18 (from 0.21).
      • Now it weighs slightly more than the Grenade Launcher. This allows you to move faster with it, to include when using a jetpack to chase down those higher lifeforms.
    • Increased base damage to 9 (from 8)
      • The weapon should feel more impactful now later in the round, creating a greater distinction from the rifle when it comes to DPS.
    • Lowered commander dropped costs to 20 team resources (from 40)
      • This should bring it into parity with other commander dropped weapon prices.
  • Prototype Lab build time
    • Fixed that the build time was 8 instead of the intended 23 seconds.
  • Eggs and Embryos (Contributed by Katzenfleisch)
    • All eggs (spawned by hives) and embryos (player evolved or commander dropped lifeforms) now have a flat 350 hp and do not mature anymore. Additionally, we have removed Marines from seeing the nutrient mist “column” effects that play on evolving players. Aliens can still see the effect on their evolving teammates.
      • We did not like how frustrating it felt for a field Marine to so easily determine which were weak evolving embryos and which were strong eggs, without commander assistance.
    • Lifeforms now share their HP relative with their Embryo. For example: While evolving, if your Embryo takes 50% damage you will hatch with 50% HP. Also: If you evolve with only 50% HP, your embryo will only have 50% of its 350 HP when you begin evolving.
      • A compromise to the aforementioned increase in HP for embryos, and because it felt horrible to shoot an embryo to 5% HP and have a 100% HP Onos hatch out.
    • Both eggs and embryos can now be healed.
      • This just felt natural to finally have, and fitting with the relative HP changes. It also can make egg-locking slightly more difficult to achieve.
    • Regardless of the damage eggs take, respawning Skulks will always hatch with 100% HP.
      • This will ensure a Hive room under attack can still respond accordingly with respawning players.
  • Default Alien Vision Changes
    • Players and structures on Marines and Aliens now have separate colors
      • During chaotic engagements with teammates involved, it was easy to lose your target with only a screen full of orange. Now Marine structures are dark blue but Marine players are still the same color (red-orange) and Alien structures are now tinted green and Alien players have a faint green outline. Hive Vision outlines now dim depending on if the highlighted player is through a wall or not. If it can damage you, it will be red-orange like a Marine.
Tweaks / Improvements
  • Added Commander skins for owners of the catalyst pack:
  • Added the animated Haunted Babbler shoulder patch:
    • Play 5 rounds during the remaining halloween season to unlock it!
  • The location caches for lights, reflection probes, and emissive props will now be calculated at map load, rather than as power points first come into relevancy for a player.  This prevents hitches in the early game of the first round of each map change.
  • Flinch animations have been removed from all players, Alien and Marine alike.
    • The blending of these animations were causing slight Client / Server desynchronization resulting in inaccurate hit feedback occasionally, and they were barely visible during typical engagements.
  • Removed the key binding to hide/show player names on the minimap (Contributed by Handschuh)
  • Modified structure extent boxes used for checking placement validation to more closely match the model. This is an improvement, but does not fix all cases.
Sound Effects / General Audio (Thanks Sweets!)
  • Removed all Alien idle sounds
    • Idle sound triggers were unreliable and difficult to predict. Most idle sounds were based on speed with an arbitrary cooldown time. A fast moving player would unknowingly play an idle sound at a time which would betray their position unintentionally. Additionally, leaving the sound turned on in 1st person only would be confusing, leading the player to believe they are making idle sounds that could be audible to the enemy.
  • Lerk Gliding
    • To prevent Lerk gliding from being completely silent after the removal of idle sounds, the 1st person sound you typically hear while gliding as a Lerk is now audible to all players. It will increase in volume slightly based on your speed. The range is very short. It is designed to allow shotgunners to flip around and respond to the Lerk sound at the very last second rather than responding only after receiving 2 bites, if they are paying attention in a quiet environment.
  • Fade Blinking
    • Sound added for all players while remaining in Ethereal form. (holding down the Blink key)
  • Audio for the Refinery buckets pouring in Smelting have been turned off for the time being until a difficult bug can be resolved.
  • Fixed issues with input handling that occurred at consistent ~80 fps or lower, resulting in ignored input commands and frame hitching. This fix makes user input consistent regardless of framerates. (Thanks Matso!)
  • Fixed issue with Gorge belly slide sound cutting out and playing inconsistently.
  • Fixed Alien regeneration sound not consistently playing when alien lifeforms or structures are healed.
  • Fixed that hydras could still shoot if they were completely inside of a clog.
    • Key word: completely. If you can see it, you can kill it.
  • Improved scenarios where commanders could execute multiple actions simultaneously that were intended to be single-use only.  For example, alien commanders could upgrade 2 or more hives at once to crag hives, or ink with more than one shade at a time.
    • More often than not these actions were done on accident, wasting resources and even having permanent repercussions (in the case of the hive type). There is still an edge case that allows you to upgrade two hives with the same hive type, but the primary means has been resolved.
  • Fixed that the Marine commander’s cursor would vanish if the player opened the main menu before the chair had fully closed around them.
  • Fixed that some players still got the summer gorge patch notification while not being able to unlock it anymore.
    • That lazy gorge on the inner tube wouldn’t hush up about summer never ending on their world.
  • Fixed some server/client desync issues with the flinch animation which could cause hit registration false positives
  • Fixed the marine builder tool animation flickering occurring while building structures from certain angles (Contributed by Katzenfleisch)
    • IronHorse is forever in Katzen’s debt for fixing his #1 most hated bug of all time.
  • Fixed that some players got beaconed when they were already in the target room (Contributed by Katzenfleisch)
  • Fixed that updating the game to a newer version (when a patch releases) and immediately connecting to a server actively playing on a custom map could cause an invalid files error.

  • Biodome (Contributed by pSyk)
    • Improved stairs in Bridge so Skulks can use the gap between them.
    • Fades can now use the gap under stairs for the lowest staircase in Bridge.
    • Improved performance of Low Lights setting
    • Improved overall performance in multiple locations by optimizing occlusion culling and lighting.
    • Map wide tweaks to Commander view to reduce visual clutter, which should make dropping structures and commander abilities easier from multiple viewing angles.
    • Fixed several misaligned textures and props
  • Descent (Contributed by Zavaro)
    • Removed Launch Bay – Shipping vent to prevent alien mobility and cheesing
    • Removed Monorail – Water Treatment vent to prevent alien mobility and cheesing
    • Removed Shipping – Hydroanalysis vent on South side of room as it was unnecessary as well as an annoying spot for Gorges to prevent Marines from ever feeling safe in Hydroanalysis
    • Added additional Shuttle Bay – Gravity vent for flanking and escape
    • Added Gravity – Shipping vent for lifeform escape
    • Added Water Treatment – Silo vent for alternate Alien path
    • Removed Hydroanalysis broken glass tube to prevent near invincible shotgun Marine positioning, is now the “unbroken” asset
    • Added pipe and cables to block line of sight from northern Hydro vent entrance to
    • prevent Gorges from Bile Bombing structures from an invincible spot (Thanks, Psyk!)
    • Broke down catwalk in Shuttle Bay – Gravity hallway to increase marine speed to the top
    • Increased size of Nebula sign in Receiving northward to better block LOS to Receiving-Hydro staircase
    • Broke glass and opened door of kiosk in Receiving to offer some additional way into/out of Shipping
    • Broke glass on rounded corner on upper level of Gravity to give line of sight to vent for marines to kill escaping aliens
    • Removed crates and a support beam to upper Shipping to make the area less cluttered and better for movement in combat
    • Added reflective glass reflections and geo to props that lack that shader
    • Changed the signs in Plaza and other areas to have proper aspect ratios
    • Fixed a number of areas with misaligned textures and holes
    • Removed a bunch of lights that were inside the walls in both vanilla and NSL lowlights
  • Refinery
    • Fixed misaligned textures around Containment tech point
    • Fixed areas where structures could not be built
    • Fixed cyst several placement bugs in multiple location
  • Fixed all NS2 tools always allocating 2GB of memory.
  • Updated GUI framework used by all tools.
    • This significantly increases their stability! No longer does using the Cinematic Editor feel like you’re blindly defusing a sentient bomb with every mouse click, waiting for it to crash just because it knew you forgot to save your work and wanted to watch you suffer.
  • Editor
    • Fixed startup crash issue when attempting to initialize a sound device.
    • Fixed a memory leak in the prefab tool that would occur whenever a prefab was placed.
    • Fixed an issue that would cause static props that were mirrored to not properly generate pathing mesh on top of themselves.
    • Lights are now filtered for selection according to their type (spotlight, point-light, and ambient-light), rather than all lights being filtered together.
    • Added a reflection probe selection filter.
    • Added a CommanderInvisibleNonCollision group (Contributed by Nin)
  • Cinematic Editor
    • Added support for the Edit and View viewport cameras to be saved in cinematic files automatically.
  • Crash dumps are now compressed before being uploaded and now have an ID that can used when reporting an issue. Click the “Copy GUID” button on the crash dump dialog window, or see your “%appdata%/Natural Selection2/dumps/dumplog.txt” file
  • Increase the amount of data captured in crash dumps to try and help track down the Lua stack corruption crash.
  • Changed how some of the engine’s Lua bindings are generated, to work around the Lua crash (seems to reduce them but not entirely fix the issue)
  • Fixed the steam branch name not always being written to the log correctly
Known Issues
  • Tools
    • Some of the tools may crash when moving/dragging their sub-window panes outside the main program window.
  • Client Crashes
    • We continue to look into our recent crashes and have made some adjustments through client only updates – as well as this patch – to both help us better locate the issue and resolve it. This continues to be the top priority of our team and we have contracted FSFOD to assist in resolving these crashes and enhance our crash data gathering tools.
18 comments Read more


"NS2 is a genius mash of Counter Strike and Starcraft"
"This is getting close to my idea of the ultimate game"

About This Game

Natural Selection 2 pits alien against human in an action-packed struggle for survival. Wield devastating weaponry as a Frontiersman marine, or become the xenomorph as a deadly Kharaa lifeform.

Strategy Meets Shooter

Natural Selection 2 is a First Person Shooter and Real Time Stategy game rolled into one! Each team, alien and human, has a Commander. The Commander looks down on the battlefield and issues orders, places structures, collects resources, researches technology, and deploys abilities.

Here are some gameplay examples: A human Commander could drop health packs and ammunition to a trapped marine squad, and deploy sentry guns to help them defend their position. Or an alien Commander could grow a new Hive to spread infestation throughout newly captured territory, allowing more alien eggs to spawn...

Two Unique Sides

Aliens players choose to evolve into one of five lifeforms: The fast, fearsome Skulk can run on walls and deliver massive damage with its jaws. Lerks fly and deploy gasses to support their teammates in battle. Gorges heal other lifeforms and build tunnels, hydra turrets, walls, and other tactical structures. Fades blink in and out of battle, picking off marines with giant scythes. Finally, the giant Onos is so massive and so tough, that even entire marine squads can't take it down.

Marines wield rifles, shotguns, grenade launchers, pistols, and other weapons. Cluster grenades can clear ventilation shafts of sneaky Skulks, flamethrowers make short work of alien structures and infestation, and boosts dropped by the Commander increase combat effectiveness.

When attacking on foot doesn't cut it, marines can construct hulking Exosuits wielding miniguns and railguns, and equip jetpacks for high speed assaults on alien Hives.

Long Term Development

Natural Selection 2 receives constant updates. This year, 2016, Unknown Worlds continues to develop new features, content, and improvements.

Mod Tools Come Standard

Natural Selection 2 comes with all the tools we used to make the game. All game code is open source. That means you can create, and play, an endless variety of mods. Publish, share, and download mods from the Steam Workshop, and automatically download mods when you join modded games.

Digital Deluxe Edition

Digital Deluxe Edition includes:

  • Official Soundtrack - 1 hour of tribal, industrial music composed by David John and Simon Chylinski
  • Digital Art Book - 40+ pages of art by Cory Strader, including environments, creatures, weapons and more
  • Exclusive in-game marine model - Exclusive in-game marine model - A new marine model with custom visor and armor plating
  • Exclusive Wallpapers and Avatars - Unique views of the NS2 universe by Amanda Diaz

System Requirements

    • OS:Windows Vista 64-bit or newer
    • Processor:Core 2 Duo E6700 (2.66 GHz) or better
    • Memory:4 GB RAM
    • Graphics:DirectX 9 compatible dedicated video card with 1 GB VRAM and support for Shader Model 3 (e.g. AMD X800, NVidia 8600 or better)
    • DirectX®:9.0
    • Hard Drive:12 GB HD space
    • Other Requirements:Broadband Internet connection
    • OS:Windows 7 64-bit or newer
    • Processor:Core 2 Quad Q9650 (3 GHz) or better
    • Memory:8 GB RAM
    • Graphics:DirectX 9 compatible dedicated video card with 1.5 - 2 GB VRAM (AMD 5770, NVidia GTX 450 or better)
    • DirectX®:9.0
    • Hard Drive:12 GB HD space
    • Other Requirements:Broadband Internet connection

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