This is a Warhammer 40k total conversion for OpenXcom, based on an earlier space marine mod by Ryskeliini. As Force Commander for the Imperium of Man on a planet beseiged by Chaos, you must find a way to end the Warp Storm and purge your world!

By Ryskeliini, bulletdesigner, ohartenstein23, and many contributors from the OXC forums


  • Download and install OpenXcom Extended (OXCE) by Meridian and Yankes
  • Run OXCE after copying the UFO files to generate the user/mods folder
  • Download the 40k files, and unzip into the mods folder
  • Run OXCE, go to Options > Mods and select "40k" from the drop-down menu at the top
  • (Optional) Check the language setting under Options and set it to "en-US"
  • (Optional) Turn on the Stat Strings mod under Options > Mods
  • (Optional) Turn on the Chapter Change mod under Options > Mods to change the look of your Space Marines to the Imperial Fists Chapter


  • Save any current campaign in the Geoscape. Loading a Battlescape save from a previous version is more likely to cause bugs and crashes, and is not recommended.
  • Remove the previous version's 40k folders from your OXCE mods folder.
  • Download the new version's files and unzip into the mods folder. Your previous saves should be compatible if made during the Geoscape.


  • Big props to Ryskeliini for the space marine stuff and Dixone for the help
  • Used a lot of maps from Terrainpack so special thanks to Hobbes also so help on side


Sprites, sounds, maps, ruleset code etc:

  • All around thanks to everyone, I used lot of stuff from other mods for reference and change it to 40k universe
  • Background images from various internet sources


3 of 48367 (2 today)ohartenstein23


OpenXcom Extended (OXCE)







doctor_medic @doctor-medic

Pretty good mod,it might not have the depth of content of mods like xpiratez or final mod pack but that allows it to focus more on specific aspects and refining them instead of quantity over quality.

ohartenstein23 @ohartenstein23

The original 016 release had a bug that had a chance of causing the wrong retaliation mission to occur - please either re-download or replace the alienRaces_40k.rul ruleset file with the one attached to this post:

Guest @guest

The names are wrong in the version i downloaded it (droppods=skyranger,stormtalon=interceptor)

ohartenstein23 @ohartenstein23

This issue is common when your operating system's default language is UK or GB English - the mod only supports US English right now. Go to the Options menu in the game and set the language to en-US.

Guest @guest

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prograde @prograde

Absolutely wonderful mod, even with the occasional quirks. I have a few concerns regarding the balance early on in the game (especially on lower difficulties when I always find myself getting swarmed by chaos raptors before having a chance to get to the mk7 tac armor).

I'd be very interested in enlisting my help in testing the game for bugs and balance!

ohartenstein23 @ohartenstein23

We've reworked the starting tech a bit so access to your first set of MK7 armor should be easier - when you research a marine "strategy," you unlock one of the variants. You can also always retreat from an enemy that's too tough, sometimes it's better to regroup and try again later.

We welcome more feedback, keep playing and letting us know what you think, either here or on the OXC forums:

TheDeparted @thedeparted

I would like to share a few thoughts with you after playing the mod for 4-5 hours. Please be advised that I'm a total noob at xcom:

1. It's one of the most polished mods I've ever played; the music is great, the sounds effects are on spot, and the gameplay is xcom;
2. The game crashes when trying to use the assault bike;
3. Isn't it a bit pointless to use Guardsmen once you've unlocked the Space Marine? (A suggestion if I may: the SM might use two spaces instead of one in the "Sky Ranger")

Thank you for a wonderful experience!

ohartenstein23 @ohartenstein23

Thanks for your feedback - I replied to your post on the forums about these points here:
The crash should be fixed in the next version (015).

TheDeparted @thedeparted

10x for your reply. much obliged. Is there any way to help the team? I suck at programming, but I'm fairly decent at editing text.

ohartenstein23 @ohartenstein23

If you'd like to do some proofreading of the in-game text, we'd appreciate it!

I've been working my way through the text in the file 40k/Ruleset/extraStrings_40k_us.rul, if you load it in a text editor, you can find the point up to where I've been proofreading. Send me any of the strings you've edited and we'll look at using that to update the in-game text.

TheDeparted @thedeparted

Cool. will do. Which text editor do you prefer/recommand?

ohartenstein23 @ohartenstein23

Notepad++ works pretty well for OXC rulesets, Visual Studio Code is free and there's an OXC ruleset validator for it:

Mostly anything that does plain text and doesn't have automatic formatting.

TheDeparted @thedeparted

The revised text is here.

TheDeparted @thedeparted

K. I'm on it.

Guest @guest

Amazing mod!

ohartenstein23 @ohartenstein23

Glad you're enjoying it!