Lambda Wars is now a free standalone mod on Steam: Steam Store (December 2014)

Lambda Wars (formerly called Half-Life 2: Wars) brings the struggle between the human resistance and their Combine overlords to a multiplayer real-time strategy setting. The Lambda Wars beta only requires Alien Swarm installed to play. It features 3 multiplayer game modes: Sandbox, Annihilation and Overrun, showcasing the Rebels and Combine playable factions and a full-fledged RTS interface and HUD. There is also a singleplayer tutorial and a handful of singleplayer missions.

As of December 2014, we have released the game on Steam as a free, standalone mod. This means you DO NOT require Half-Life 2, Alien Swarm or any other Source game to download and play Lambda Wars on Steam.

For questions, comments, suggestions, and support for any of our past or upcoming betas, visit our forums or steam community hub.

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Blog RSS Feed Report abuse Latest News: Lambda Wars Beta HL2 RTS Mod Released For Free on Steam

8 comments by Ennui on Dec 9th, 2014

We are proud to announce that Lambda Wars is now officially available for FREE to download on Steam! For those of you unfamiliar with us, we are a completely free Half-Life 2 real-time strategy (RTS) mod formerly known as HL2: Wars and have been in development for over six years with public releases throughout that time. This is our first official Steam release after successfully passing through Greenlight in January 2014.

Our Steam beta release brings with several major changes from our last version, most notably a complete overhaul of the in-game menu UI systems and revising our multiplayer matchmaking system to take full advantage of everything Steamworks offers. On top of that we have also spent a lot of time as usual on improving the mechanics and gameplay balancing and fixing a litany of bugs large and small. Below you can see some of the major UI work that has gone into this release:


You can go ahead and download it free on Steam right now by visiting our Steam Store page - thanks to Valve's fantastic support of free mods we are happy to announce that you do not need to own HL2 or any other Source games to play this for free! If you have any problems please post in the support section of our forum community.

Why still beta, you ask? Before we release Lambda Wars 1.0 we want to hear YOUR feedback. What works? What doesn't? What could be improved or added or removed? We want to hear from YOU, whether it's on our Steam Community Hub, our discussion forum, Facebook, Twitter or ModDB profiles. If you like what you see, do us a huge favor and spread the word!


We want to take this moment to thank all of the loyal players who have provided us with feedback over the years, as well as everyone who supported and voted for us in our Greenlight bid and got us into the top ten mods of the year in 2008 and 2010 for ModDB's MOTY vote. Most of all, thanks to Valve Software for being supportive and permissive and allowing us to use their IP and materials to build and distribute a RTS mod of the Half-Life universe we all love so dearly.

Download Lambda Wars for free now on the Steam Store. If you like it, show it by supporting us on Steam Community, our discussion forum, Facebook, Twitter and ModDB and by providing your valuable feedback, bug reports or support requests on our official community forum.

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Lambda Wars 2.3.6 FULL EXE

Lambda Wars 2.3.6 FULL EXE

Jun 9, 2014 Full Version 13 comments

The newest version you can now get directly on steam, completely free, no other games needed. Install Instructions: 1. Run the Installer and follow the...

Lambda Wars 2.3.6 FULL 7z

Lambda Wars 2.3.6 FULL 7z

Jun 9, 2014 Full Version 2 comments

Install Instructions: 1. Extract contents into your sourcemods folder (default location: C:\Program Files (x86)\steam\steamapps\sourcemods). 2. Restart...

Lambda Wars 2.3.5 7z PATCH

Lambda Wars 2.3.5 7z PATCH

May 10, 2014 Patch 4 comments

Install Instructions: 1. Extract contents into your sourcemods folder (default location: C:\Program Files (x86)\steam\steamapps\sourcemods) and overwrite...

Lambda Wars 2.3.5 FULL EXE

Lambda Wars 2.3.5 FULL EXE

May 10, 2014 Full Version 6 comments

Install Instructions: 1. Run the Installer and follow the instructions. 2. Restart steam. 3. "Lambda Wars" should now appear in your games list. If you...

Lambda Wars 2.3.5 FULL 7z

Lambda Wars 2.3.5 FULL 7z

May 10, 2014 Full Version 0 comments

Install Instructions: 1. Extract contents into your sourcemods folder (default location: C:\Program Files (x86)\steam\steamapps\sourcemods). 2. Restart...

Lambda Wars 2.3.4 FULL 7z

Lambda Wars 2.3.4 FULL 7z

Feb 23, 2014 Full Version 1 comment

Install Instructions: 1. Extract contents into your sourcemods folder (default location: C:\Program Files (x86)\steam\steamapps\sourcemods). 2. Restart...

Post comment Comments  (1420 - 1430 of 1,977)
Shadowbounty Aug 1 2009, 11:46am says:

When is that multiplayer thing coming, you said it would be ready in the next two or something months, it's been longer than that now

+3 votes     reply to comment
Ennui Creator
Ennui Aug 3 2009, 11:40pm replied:

To be honest, we pretty much scrapped the MP demo idea, it was only going to be a little MP game where you can fight each other with antlion swarms, instead we've just been working on the full Beta 1.0 which will have fully implemented multiplayer and a shitload of other improvements. Before too long we are going to write another newspost, the thing is that most of our progress is not visual (code/design) so we don't have much pretty stuff to show off.

+2 votes   reply to comment
Discrate Aug 2 2009, 4:56pm replied:

No, if you read the last news post correctly, a MP demo may be out in the next 2 months. Things change, which they have, so you will just have to wait longer.

+1 vote     reply to comment
[λG]_BiO Jul 26 2009, 8:53am says:

This game looks awesome! Excelent work, keep it up!

+1 vote     reply to comment
Shadowbounty Jul 25 2009, 1:49pm says:

Great mod. i look forward to playing the latest release

+1 vote     reply to comment
wav Jul 15 2009, 3:59pm says:

It's surprisingly not dead. Check the forums they say they won't bother to post a update until they get their multilayer beta working.

+1 vote     reply to comment
AntiViper Jul 15 2009, 6:33pm replied:

This is true, we dont believe posting an untextured weapon render every day is a good news update. A fully functional multiplayer release would be something worth checking out.

The new version is progressing well, but there is still alot of work to do. A better timescale will be known as things move on further.

If you want to talk about anything more check out the forums or IRC channel.

+2 votes     reply to comment
zackiller25 Jul 20 2009, 2:34pm replied:

Isn't it more important, to get more support and fan base, then make people think it dead?

+1 vote     reply to comment
Ennui Creator
Ennui Jul 22 2009, 4:29pm replied:

We're more worried about working on the mod than getting a fanbase. People will play it whenever we release it, no need to get people excited when we're still a long way away from another release.

Hopefully we'll have beta 1.0 by the end of 2009. That's ABSOLUTELY not a promise.

Also obviously we aren't dead, just quiet publicly :)

0 votes   reply to comment
AntiViper Jul 22 2009, 5:07am replied:

For us the important thing is to get a fully functioning, smooth running multiplayer release done. At that point there will be some real content to get a fan base going. As mentioned before the current release is more of a proof of concept.

If anyone thinks the project is dead they only have to check the forums or IRC to see its not. If they don't check them out then i am sure they will see the mod on a fansite when the release is out.

+1 vote     reply to comment
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Released Sep 25, 2012
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Highest Rated (14 agree) 10/10

Very original, very fun, and i see a LOT of great potential for this mod in the long run.

Nov 27 2010, 2:33pm by Heroman117

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