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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High Voltage! We expected this much! (c) FIFA year after SHW (Seven Hour War)
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 14 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  (60 - 70 of 1,980)
Evil-Pyro Jul 3 2014, 11:35pm says:

Is that game was in the gl?

+2 votes     reply to comment
Reborn:X Jul 29 2014, 2:42pm replied:


+1 vote     reply to comment
Su[)az][mA Jun 30 2014, 7:34am says:

hah nice going guys! chilled in your IRC a little long ago if you remember :P

0 votes     reply to comment
Стрелок Jun 30 2014, 1:59am says:

Incidentally conveyor can transport other than infantry, armored and Strider!!!

+2 votes     reply to comment
Стрелок Jun 30 2014, 1:55am says:

I know what I say spoils the game balance, but it would be cool to have on the Alliance adopted by all types of vehicles (armored personnel carrier, helicopter, attack, transporter). After all, for the rebels, too, can come up with something.
What do you think? Sorry for bad english.

+3 votes     reply to comment
Firelord475 Jun 29 2014, 9:19pm says:

Would it be possible to change what kind of headcrab is fired from a headcrab canister launcher?

+3 votes     reply to comment
Guest Jun 29 2014, 5:13pm says:

This comment is currently awaiting admin approval, join now to view.

LonelyAmerican Jun 26 2014, 6:08pm says:

I feel that the Sandbox editor needs some improvement aswell. It is fun to be able to place objects anywhere you want and mess around, but players should also be able to save custom, modified/created maps for use in other gamemodes. This would probably be helpful considering some may want to continue their work after a match. Anyone else agree? :D

+1 vote     reply to comment
Pigbear2 Jun 24 2014, 6:51pm says:

How do you rotate buildings? is this just not implemented or am I stupid?

+2 votes     reply to comment
Sander Creator
Sander Jun 27 2014, 5:32pm replied:

The main reason it's like this is because the Navigation Mesh has square sized navigation areas aligned to the world grid ( Placed buildings would break these areas in a weird way. Unless we replace it, I don't think it's acceptable or worth it to have large rotable buildings.

+1 vote   reply to comment
ceu160193 Jun 25 2014, 12:50pm replied:

You can rotate only defensive buildings, rest of them can not be rotated.

+2 votes     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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