Natural Selection is an action-strategy game for the PC. It is a "Half-life modification", which means it is written on top of the Half-life game engine. "Mods" are a new sort of underground game development that enables small teams to create games using the technology of existing games. This means less expensive and lower risk game development, which allows experimentation and innovation. This arrangement also implies that "mods" are made as art, not for making money. When complete, Natural Selection will be released for free to all owners of Half-life, which is required to play Natural Selection.

Game summary

Multiplayer-only Half-life mod where one team plays marines and the other plays aliens. The humans must keep their cool and work together to assault an alien-infested spacecraft or colony. Marines vs. marines and aliens vs. aliens scenarios are also supported.

"First-person strategy" with a real resource model and consequences for actions. Both sides are genuinely different and together they accommodate different play styles:

Marines::Fighting skill is less important, strategy and communication take its place. Playing as a marine will be a tense experience with methodical planning and strategy, interrupted with action.

Aliens::Playing as an alien will be an intense action experience, rewarding reflexes and alien heroics. Communication and coordination don't require typing.

Accessible, fast, mouse-driven interface: no keys beyond those used in Half-life needed.

Simple to learn and play, it is hard-core action/strategy for a mainstream audience.

Innovative social dynamics lead to memorable games.

Atmospheric indoor sci-fi environments full of steam, smoke and ambient soundscapes

Natural Selection is out, go get it already! :P

Recent Changlogs:
Version 3.2
Version 3.1
Version 3.0

The team is now working on a version for Half-life II and will post news here when ready.

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Blog RSS Feed Post news Report abuse Latest News: Natural Selection Source Code Released!

2 comments by JPolito on Jan 23rd, 2014

Natural Selection Source Code Released!

Posted by Hugh
Original news post available here:
Natural Selection Source Code

Back in 2002, Natural Selection was released…

Since then, lots has happened. Unknown Worlds was formed and NS2 was released, reaching multiple times the number of players the original mod did. Charlie, the creator of NS, has come so far that he’s now working on a new game: Subnautica.

But we will never forget what started it all. Today, we are proud to announce that Natural Selection Source Code is now available to anyone, free of charge. Head on over to GitHub to get it. It’s not ‘open source’ – There is some legal hoo-ha that prevents that. But it is all there.

Natural Selection 1

Got balance?

You can use the NS source code to make your own version of the original game, fix problems with it, make new problems, or just see how the game worked.

We hope you enjoy tinkering with it. NS was one of the greatest mods of all time – And we can’t wait to see what you are able to do with it.

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Natural Selection v1.0 plus patch v1.04 (outdated)

Natural Selection v1.0 plus patch v1.04 (outdated)

Mar 26, 2013 Full Version 0 comments

It's an old version of NS, dated by 29th October of 2002. Uploaded for historical and collectors' purposes, because it's hard to find on internet now...

Natural Selection v2.0 Dedicated Server (outdated)

Natural Selection v2.0 Dedicated Server (outdated)

Mar 26, 2013 Server 0 comments

It's an old version of NS, dated by 30th July of 2003. Uploaded for historical and collectors' purposes, because it's hard to find on internet now. Requires...

Natural Selection v2.0 Client (outdated)

Natural Selection v2.0 Client (outdated)

Mar 26, 2013 Full Version 0 comments

It's an old version of NS, dated by 30th July of 2003. Uploaded for historical and collectors' purposes, because it's hard to find on internet now. Requires...

NS 3.2 Hungarian Translation with voices

NS 3.2 Hungarian Translation with voices

May 18, 2009 Patch 10 comments

The Half-Life mod , called Natural Selection is basicly ENGLISH, but this one is enables the Hungarian Translation. Ha nem értesz angolul, akkor ezt...

Natural Selection v3.2 Installer

Natural Selection v3.2 Installer

Mar 2, 2007 Full Version 65 comments

The full client installer for Natural Selection v3.2. Check out the full changelog here.

Natural Selection v3.2 Server

Natural Selection v3.2 Server

Mar 2, 2007 Full Version 7 comments

The dedicated server zip for Natural Selection v3.2. Check out the full changelog here

Post comment Comments  (20 - 30 of 436)
CriizPixel Nov 6 2012, 9:38am says:

I cannot open this mod in a few second close U.U

+2 votes     reply to comment
Gonzalord Apr 28 2013, 6:49pm replied:

Happned 2 me bro, just add a new shortcut in your desktop for Half-Life.exe and add -game ns
then you already start in the Mod with no crash at start
If problem persists then you must Update your Half Life game to a newer version ;) google it

+1 vote     reply to comment
TheUnbeholden Oct 31 2012, 10:44am says:

Natural Selection 2 has been released, and a full fledged game this time around

+1 vote     reply to comment
POD_ILL_bot_0 Oct 17 2012, 1:15pm says:

I see 10-20 servers every day.

+1 vote     reply to comment
iamcreasy Sep 20 2012, 9:31am says:

Is there any live server? The server list is empty when I search for one.

+1 vote     reply to comment
GamerPlayer Sep 9 2012, 1:34pm says:

They should really have this on Desura. I was expecting it to be on Desura, but it sadly wasn't there.

+1 vote     reply to comment
JuQu Sep 16 2012, 11:41am replied:

This should be in Greenlight... >:o

+5 votes     reply to comment
AyCe Aug 23 2012, 10:41am says:

Few servers, fewer players, extreme pings only, but it still ROCKS :D

+1 vote     reply to comment
Ravious Aug 7 2012, 10:12pm says:

I remember trying this out quite a while back, but there was such an extremely low amount of players. Has there been an influx of people due to NS2, or are the shelves still empty?

+1 vote     reply to comment
HazarD. Jul 1 2012, 2:10pm says:

Love it!!

+2 votes     reply to comment
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Released Jun 2007
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