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.
Recent Reviews:
Very Positive (50) - 90% of the 50 user reviews in the last 30 days are positive.
All Reviews:
Very Positive (3,050) - 94% of the 3,050 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 (181)

January 14

Hungry for some competition?

Hello there, strategists!
Two weeks ago, during the New Year, we hosted a tournament with a prize pool that was announced only in Discord. The experiment went well and so now we have a new tournament coming in hosted by one of our community members, Wizard Cat!

Please make sure to join our Discord server so you don't miss such opportunities! In fact, you need to be in our Discord in order to take part in it.

Anyway, now to the announcement itself.

Feeling thirsty for some more tournaments?
Come play more with Wizard Cat as the host for the upcoming tournament!

Starting this Friday, join a double eliminations tournament (that's 2 brackets: winners and losers).

The maps are limited to 4 player maps (for example, base4, mine, city16 and such are allowed).

Mail with the following info:

Title of the mail: "Tournament applicant"
- Discord tag
- Steam profile link
- Time zone

The games will be streamed at and the casters will be:
Wizard cat
and me (Mr. Darkness)

If you have any questions, forward them to wizard cat on Discord.
7 comments Read more

December 5, 2018

Let's do our part

It has always been known that the evil exists. That it exists somewhere around the corner.

Once upon a time Lambda Wars used to be a dark place filled gray souls working on it. But there was the light. The light that brought future to the developers and players of Lambda Wars altogether.

But this light may soon perish if we do not defeat the evil. This evil must be taken care of.

Yes, my strategists. Yes. I am talking about the one and only Indian evil that is trying to take over YouTube. This evil is known as T-Series and the light that MUST BE ABOVE IT IS KNOWN AS PEWDIEPIE.


By clicking this link you prove to be with us, with the 9 year old army, with the bright future for us all:

Do it.

Do not fail Lambda Wars.
31 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 :(

What Curators Say

28 Curators have reviewed this product. Click here to see them.

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