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 (32) - 81% of the 32 user reviews in the last 30 days are positive.
All Reviews:
Very Positive (3,147) - 94% of the 3,147 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 (183)

March 16

The development is currently on a halt

Hey guys.

Thank you all very much for playing the game.
I wanted to let you guys know that I personally won't be able to work on the game till about May-June for several reasons:
  • My PC is currently dead (been like this for two months already);
  • I have to do my thesis;
  • Work.

Sandern is also currently very busy with his other projects, and as you may understand, the mod doesn't provide us anything for a living, so it's a lower priority for us.

Still though, I expect to work on it more when I have the time and resources for that. I love the mod and I wouldn't abandon it like that.

Also we have the community that keeps making maps (someone like MrLazy who made so many maps already, and some other community members are actually beginning on taking their part in this!).

If you guys would like to chat, feel free to join our Discord channel, I try to be as active as possible there:

So see you there!

UPD: Tyler, thanks a lot! <3
21 comments Read more

January 23

Lambda Wars mini-patch January 24, 2019 (3.11b, rev. 6577)

There has been a lot going on lately in this month, such as hosting a mini-conference (not related to Lambda Wars) in a Russian high school and a tournament with a prize pool for players.

For now there's going to be a small patch, next will have an update including MrLazy's new map. For those of you who are curious, feel free to test it on the dev branch!

- Changed the prices for control points on Lvl 1 and Lvl 2. Advanced/Professional players requested that the prices are changed for better competitive gameplay.

- Added badges for tournament players who participated and those who received respective places.

I've also included loading screens from 2017 contest, but they currently don't work as Sandern hasn't had time to work on LW yet, so that will be done later.
6 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

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

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