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  (1670 - 1680 of 1,977)
bomblol Aug 18 2008, 1:24pm says:

I was hopeful. unfortunately this mod sucks, mainly because of the horrible pathfinding. this isnt just bad, its game breaking. my person couldnt get off the stairs, no matter how close i told him to walk.

-2 votes     reply to comment
BiotecVirus Creator
BiotecVirus Aug 31 2008, 4:51am replied:

Blame valve for making a crappy nav mesh. Not Us

+1 vote   reply to comment
Nyko1229 Aug 19 2008, 4:20pm replied:

Not to be rude or anything but have you checked the versions? it's a beta..a very early beta. (The second public beta ever released), I don't know what you were expecting but this mod is no where near completion.
Path-finding is also not that easy to code...
I would say wait for the full release before forming an opinion.

+1 vote     reply to comment
bomblol Aug 20 2008, 12:36pm replied:

Yeah, sorry, I was being a ****, i was pretty ****** off at the time, i liked everything but then i couldnt get out of the house

+1 vote     reply to comment
INCWADRA Aug 17 2008, 6:27am says:

Nice mod =)

+1 vote     reply to comment
Wiweeyum Aug 16 2008, 5:54pm says:

Steam's broken for me right now, but this is the kind of mod that I'd absolutely love to play. I've wat5ched the video a number of times, and have not failed to find something cool that I hadn't seen before.

The fact that HL2 is a first person genre game, and you've done an entire RTS revamp is just amazing to me. Kudos the the 'n'th degree.

+1 vote     reply to comment
PizzaGhost Aug 16 2008, 12:21pm says:

Very good mod i cant wait for the next release

+2 votes     reply to comment
PizzaGhost Aug 16 2008, 11:50am says:

Downloading now, cant wait to play

+1 vote     reply to comment
DarkSoroush Aug 16 2008, 5:47am says:

Very nice mod. 10/10

+1 vote     reply to comment
Da_maniaC Aug 8 2008, 5:51am says:

This is truely a great concept of a mod!
And the graphics are great because you can just use the actual engine in game and not some stuck pov.
I'd love to see how you will try and balance gameplay between 2 factions!

+4 votes     reply to comment
aidas2 Aug 8 2008, 3:05am says:

lol yeah this is a great mod and I cant wait till they complete it fully and add a campaign

+5 votes     reply to comment
Megadave2003 Aug 7 2008, 12:52am says:

I try to start the game and every time it says content servers are not availible

+1 vote     reply to comment
SfcRock Aug 6 2008, 9:43pm says:

Cant Wait till the next update comes out. Its driving me crazy, how long will it take?

+3 votes     reply to comment
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Released Sep 25, 2012
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1174 votes submitted.

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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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