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  (0 - 10 of 1,972)
Guest Jun 8 2015, 4:07pm says:

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

darkyuri Apr 6 2015, 1:05pm says:

I have got problem with terrain,
terrain is black.

+1 vote     reply to comment
modmakin Mar 29 2015, 6:01am says:

A Company of Heroes veteran should easily understand this mod/game
WITHOUT the tutorial.

+1 vote     reply to comment
skullzans Feb 28 2015, 11:29pm says:

Personally i wish the antlions made a return... I loved the race... But i understand the lack of NPCs... So perhaps i make suggestions:Change the race from Antlions to Xenian Remnants and include other wildlife of xen

+1 vote     reply to comment
Soviet_Conscript Jan 25 2015, 8:16am says:

Hi, guys, do you plan adding units from Raising the Bar and Leaked Beta version of Half-Life 2?

+1 vote     reply to comment
HEVcrab Jan 25 2015, 9:19am replied:

I've suggested adding Cremator and Assassin as Combine counterparts of Flamer and Saboteur, also figured out some abilities for assassin to work well in RTS. Hopefully they will be included one day, I expect them to make nice additions to the gameplay.

+3 votes     reply to comment
Soviet_Conscript Jan 28 2015, 8:37am replied:

Ооо, так мы можем и по-русски?)

+1 vote     reply to comment
Soviet_Conscript Jan 27 2015, 2:14pm replied:

It's will be cool if we see in game more synths, like synth mortar or synth crab. And more alien units in combine army. In your plans rebels have a some kind of tank?

+2 votes     reply to comment
young_warrior Feb 14 2015, 3:36pm replied:

rebels should have vehichles, made from spare and salvaged parts (like the buggy, airboat and the muscle car)... for example, a scout car, like a small buggy with a light machinegun ontop of it, a sturdy car, like a jeep with some armor plates and a heavy machinegun on it, a "apc", like that modified van from l4d and it firepower should vary depending on the size of the platoon that it is carrying (rebels using their guns on small portholes to cover the apc) and a "tank" that can be recovered old tanks or trucks carring recovered mortars on their back!
as for the combine... well, combine mechanic and synth units that were seen before, plus some news like combine tanks a light and a heavy type, scout cars etc. etc.
btw the game looks pretty impressive, i doesn't look like it is on its beta stage, it looks like a complete game!
really fun to play!

+1 vote     reply to comment
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
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Release Date
Released Sep 2012
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1175 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

Real Time Strategy
Single & Multiplayer

Latest tweets from @lambdawars

A small update has been released which includes map updates and some bug fixes

May 15 2015, 8:51pm

We released an update containing achievements, Combine resource changes, one new map, balance changes and bug fixes.

May 11 2015, 8:28pm

Take a look at Dog's new jumping ability!

Mar 10 2015, 4:50am

We released another update 3 days ago. This update includes multiple gameplay and balance changes! Full changelog:

Mar 10 2015, 4:39am

We have released another patch which includes bugfixes, visual enhancements and map updates!

Feb 6 2015, 3:27am

A new update released containing a new map, balance updates, bugfixes and more! You can see the patchnotes here:

Jan 6 2015, 11:09am

Lambda Wars has received the editor's choice "Best Overhaul" mod of the year award! Thank you @ModDB !

Dec 24 2014, 9:40am

Lambda Wars got a wonderful write-up in @WIRED this week - thanks guys!

Dec 22 2014, 1:12am

Only 5 hours left to vote for the @ModDB Mod of the Year top 10!

Dec 20 2014, 2:00pm

Take a look at the new Rebel Partisan skin!

Dec 20 2014, 1:47pm

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