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 15 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  (10 - 20 of 1,972)
Firelord475 Jan 16 2015, 2:07pm says:

any plans for the headcrab canister to have a fast zombie or poison upgrade?

+1 vote     reply to comment
HEVcrab Jan 20 2015, 2:42am replied:

At least I've suggested that, along with infest ability for poison and fast headcrabs as well (turning bot combine and rebels into fast and poson zombies, as these headcrabs cause such body alterations that it doesn't matter if the victim was Combine or not).
This will also be useful in future zombie singleplayer mission, as a way to get fast and poison zombies for the undead army.

+1 vote     reply to comment
Cossack-HD Jan 4 2015, 1:48pm says:

First of all, thank you for the game!

Now to the stuff that makes the game better (constructive critics!) :D
In the overrun game mode, sometimes the enemy NPCs get stuck in a strange place of the map and the wave never ends.
Map Trapped, easy difficulty, zombie type. Never could get further than wave 8 because of that bug.
Map City, after some time fast headcrabs spawn above the game area (NPCs aim for something in the air but can never hit it).

Please just set time limit for each wave and if the time limit is exceeded make those NPCs die.
Or set a timer for each NPC (if it lived for 2 minutes and never hit player it should die).

+2 votes     reply to comment
Sander Creator
Sander Jan 4 2015, 5:01pm replied:

It should already be doing what you describe. After 60 seconds of no wave progress it should kill off all enemy units.

+1 vote   reply to comment
yarow12 Jan 1 2015, 9:19pm says:

It's nice to know that HL2: Wars wasn't given up on.

+1 vote     reply to comment
Guest Dec 20 2014, 2:46pm says:

I'd like to see vehicles with A.I.

For example:
-Airboat with ally piloting it
-Jeep with ally piloting it
-APC with combine piloting it
-Muscle car with ally piloting it
-Hunter chopper with combine piloting it

All of these vehicles could be upgraded (excluding the Muscle car)
as in the Airboat getting the Hunter chopper's gun, the Jeep getting the Tau cannon, the APC getting the rocket launcher, the Hunter chopper getting the machine gun, and the Hunter chopper getting the bombs.

If possible, I would love to see this added! :D

+1 vote     reply to comment
Guest Dec 20 2014, 2:37pm says:

I made a suggestion on the steam forums about a Xen faction and an HECU faction. Not now, but more as a future planned feature.

+3 votes     reply to comment
MoopTheLoop Dec 24 2014, 2:42am replied:

Why would you want to add this? This is based on Half-Life 2 not the original.

+1 vote     reply to comment
HarbingerInfinite Dec 29 2014, 3:37pm replied:

I dunno, I'd like more Factions than just Rebels and Combine, Fighting Xen and HECU sounds like fun.

+2 votes     reply to comment
mrdomosquad Dec 16 2014, 7:45pm says:

when i try and play the game it dosent let me see anything its just black on my moniter ive searched everywere but here so is their a graphics card limit or something? please help!

+1 vote     reply to comment
E.T.E.R.N.A.L. Dec 12 2014, 8:00pm says:

Great mod, but it really ticks me off how striders can be taken down with machineguns and crossbows.

+1 vote     reply to comment
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Released Sep 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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