Lambda Wars is a free standalone multiplayer Source Engine modification set in the Half-Life 2 universe that brings the war between mankind and their brutal Combine overlords to a traditional real-time strategy (RTS) setting.
User reviews:
Very Positive (64 reviews) - 96% of the 64 user reviews in the last 30 days are positive.
Very Positive (2,097 reviews) - 94% of the 2,097 user reviews for this game are positive.
Release Date: Dec 5, 2014

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Community-Made Mod

This is a free community-made modification for Alien Swarm set in the Half-Life 2 universe.

Click here to learn more about mods on Steam.

Install Lambda Wars Beta

Free Alien Swarm Mod


Recent updates View all (115)

May 12

Status Update 14 - A personal message from Songbird

Hello Strategists!

Allow me to first apologise for two things, which is:
One: I've not been posting these for two weeks now, and even this is way too late. So again, my apologies! (I do that a lot for this reason.)
Two: For the unfortunate reason I have to break to you which can be read in full here.

Let me get onto the project details of this week's update.

Community Status

Provided you've read the link I've given to you prior to this point being addressed, it means that I'm taking distance from all of my existing tasks, which also means organising the tournament. Of course anyone is free to host an unofficial tournament to tide everyone over until an official one can be realised.

Again, I want to express my deepest regrets for again not being able to organise this again.

There is no saying whether one of the developers will take over my promise to host a tournament for so long now, but one can hope right?

Development Status
(Un)fortunately all of the developers are currently caught up in school, work, university, courses, and more of that fun, which leaves most of us a bit inactive on the development front. Tying into the message Darkness said, I too have to distance myself now for an undetermined period of time ranging from 3 weeks to 3 months, but more on that can be read in the link up at the top of this post.

I can't say with certainty what's being worked on right now, but I'm sure Darkness will let you all know in due time when everyone's returning.

In closing

I've received outcries and compliments saying nobody could do a better job than I have done for the past 5 months. While I've performed my duties within this game, its community and its team with faith and a smile, I feel it's time to step aside for some time to re-evaluate my usefulness in this project. I'll remain in contact with Darkness.

Questions regarding my semi-resignation can be sent to as I have personally deactivated my e-mail account for the time being, and all incoming emails are rerouted.

I have removed myself off the title of Project Manager for the game's forums and Discord, but I'll remain a developer on the Steam Hub until my resignation gets made official by me, but that is only in the worst case "if" scenario.

In closing, I'd like to thank everyone for their continued support to the game. That has been my biggest reward, a reward no money could ever trump. I've presided over the Community as its manager with pride and joy, seeing the game becoming a flourishing hub again, with our discord having surpassed 230(!)+ members so far, and that in the course of 5 months, leaves me to wonder what we can accomplish on a much longer road.

And mostly my thanks goes out to Darkness, my support crutch and best friend through all of this, supporting me every step of the way and picking me up when I was wracked with doubt about my decisions for the Community. With his help, I've tried to make the best decisions for the game. But all I can think and hope; "Was it enough?".

Time will tell.

For now it's time to concentrate on my own wellbeing, as can be read in the thread.

Signing out,

16 comments Read more

April 28

A Message From A Developer

Hello, strategists! :SBHorse:

Without further ado, I'll get right into what I am making this announcement for.

First of all, thank you all for supporting the game! The last few days haven't been very active in terms of player count however, but my guess is it's because of the week work days. Good activity is only seen on weekends thus far.

Now, allow me to apologize. I am not able to work on the game for now, I got a lot of stuff related to studies and everything. Haven't touched games for a while too. There is a lot needed to be done and I can't really spend too much time on the development process. The game will probably be inactive in terms of development, most likely for a few weeks (give it two weeks until I report, or Songbird (aka Jake M.) reports in again).

Last, loading screens. I've received a quite a lot of them thus far and some of these were already selected for being forwarded into the game :).
Be aware that I've stopped receiving these lately, so I'd like to see some more ;).

Loading Screens:

That's all.
Stay tuned! :use:

P.S: 107 friend requests. I wonder if I can get more than my max friend list capacity even allows? lol...

23 comments Read more

About This Game

Lambda Wars is a free multiplayer Source Engine modification for Alien Swarm set in the Half-Life 2 universe that brings the war between mankind and their brutal Combine overlords to a traditional real-time strategy (RTS) setting. Lead the uprising as a commander of the Resistance or crush the rebellion as an overlord of the Combine, with both factions featuring a full host of units, abilities, buildings, research and defenses. Lambda Wars features full-fledged RTS gameplay and a robust RTS interface and is focused on multiplayer but strategic AI opponents and dedicated singleplayer missions are also included.


  • Classic real-time strategy (RTS) gameplay in the Half-Life 2 world
  • Multiplayer support and game lobby including spectator mode
  • Wide variety of maps for up to 8 human or AI players
  • Play as either Combine or Resistance (and also Antlions in Sandbox mode)
  • Full unit tech tree that allows you to command everything from Manhacks to Striders
  • Full-fledged RTS interface and HUD with everything from minimap and fog of war to unit and production building groups
  • Build production and research facilities to requisition better units and unlock abilities and upgrades
  • Defensive structures, turrets and mines help defend your headquarters and vital resource points
  • Multiple game modes
  • Singleplayer missions, tutorial map and offline AI skirmish mode

System Requirements

    • OS: Windows 7
    • Processor: Dual core from Intel or AMD at 2.8 GHz / Quad-Core Intel at 1.33 GHz
    • Memory: 1 GB RAM
    • Graphics: Intel HD Graphics, nVidia Geforce 8600GT, AMD Radeon HD2600 or better
    • DirectX: Version 9.0c
    • Storage: 4 GB available space
    • Sound Card: DirectX 9.0c compatible sound card
    • Additional Notes: These are the minimum requirements to be able to run on lowest settings
    • Memory: 3 GB RAM
    • Additional Notes: Being able to go easy on us devs for all the bugs and glitches :(
Customer reviews Learn More
Very Positive (64 reviews)
Very Positive (2,097 reviews)
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