OpenXcom Co-op Mod v1.32.0 – Beta Release (Windows)

1. Updated OXCE build from 7.15.0 to 8.4.2.

2. Added 64-bit Linux support (OpenXcomCoop-x86_64.AppImage).

3. Improved AI synchronization for movement, waypoints, mind control, melee, explosions, damage, throws, and shooting in Battlescape.

4. Fixed cases where client units could fire more shots than intended.

5. Fixed unit selection issues in Battlescape.

6. Fixed end turn screen so it is now displayed correctly on the client.

7. Fixed time synchronization so only the host can control time.

8. Added a multiplayer option to completely disable time sync.

9. In Campaign PvP, UFO player bases are now disabled and hidden, while XCOM bases remain visible to both players.

10. Fixed OXCE 8.4.2 issues that broke 7.15 features, affecting bases, soldiers, and Co-op menu UI button positions.

11. In PvP, other player’s units now belong to a hostile faction, not the same player faction.

12. In PvP, unit spotting was added (work in progress).

13. In PvP, reaction shooting was added.

14. In Battlescape, end turn screen now correctly updates explosions and closes doors on the client on the next turn.

15. In Battlescape, unit damage synchronization was fixed in cases involving Power Source explosions.

16. Missions now end correctly on the client.

OpenXcom Co-op Mod v1.32.0 – Beta Release (Linux)

1. Updated OXCE build from 7.15.0 to 8.4.2.

2. Added 64-bit Linux support (OpenXcomCoop-x86_64.AppImage).

3. Improved AI synchronization for movement, waypoints, mind control, melee, explosions, damage, throws, and shooting in Battlescape.

4. Fixed cases where client units could fire more shots than intended.

5. Fixed unit selection issues in Battlescape.

6. Fixed end turn screen so it is now displayed correctly on the client.

7. Fixed time synchronization so only the host can control time.

8. Added a multiplayer option to completely disable time sync.

9. In Campaign PvP, UFO player bases are now disabled and hidden, while XCOM bases remain visible to both players.

10. Fixed OXCE 8.4.2 issues that broke 7.15 features, affecting bases, soldiers, and Co-op menu UI button positions.

11. In PvP, other player’s units now belong to a hostile faction, not the same player faction.

12. In PvP, unit spotting was added (work in progress).

13. In PvP, reaction shooting was added.

14. In Battlescape, end turn screen now correctly updates explosions and closes doors on the client on the next turn.

15. In Battlescape, unit damage synchronization was fixed in cases involving Power Source explosions.

16. Missions now end correctly on the client.

OpenXcom Co-op Mod v1.31.0 – Beta Release

Changelog 2025/11/01

During the past month, synchronization across the Battlescape has been reworked almost completely. AI synchronization is still in progress, so a few issues may remain and will be fixed later.

Shooting, movement, and death now synchronize much more reliably between players. Previously a shot could hit the UFO for one player but miss for the other, or an XCOM soldier could appear alive for one player but dead for the other. This “ghost soldier” problem has been fixed.

Projectile coordinates now synchronize to ensure that hits register the same way for everyone. Tile damage is synchronized as well. Panic and berserk states are synchronized so units walk to the correct tile and can drop their weapon correctly.

The issue where units did not move anywhere when path preview was enabled has been fixed.

The host now fully controls the client during AI turns, and the client no longer runs its own logic. This eliminates cases where units teleported or moved incorrectly.

In PvP the opponent no longer hears footsteps when a player is sneaking. The end-of-battle screen has been corrected. If the UFO side wins it shows Craft Lost, and if XCOM wins it shows UFO is recovered.

The settings menu now includes a Multiplayer options section. You can set a key to open chat and allow research synchronization in campaign mode. Many players have felt research synchronization is too strong, so it is now a setting. More options may be added later.

Some players experienced melee attacks and shots always missing. This was caused by random generator synchronization happening at the wrong time. That synchronization has been removed, and the random generator now behaves the same way as in the original X-COM.

Next we will continue improving AI synchronization and show the end turn screen on the client. Our goal is to keep multiplayer changes as close as possible to the original X-COM behavior.

OpenXcom Co-op Mod v1.30.0 – Beta Release

Changelog 2025/10/11

1. Fixed an issue where duplicate unit IDs could assign positions and items to the wrong unit, causing sync errors. You need to abort the mission and start a new one for the fix to take effect. You do not need to start a new campaign.

2. Fixed MonthlyReport not appearing for the second player

3. Fixed UFOs sometimes not appearing and crashing the game

4. PVP campaign removed message STR_UNABLE_TO_USE_ALIEN_ARTIFACT_UNTIL_RESEARCHED and UFOs can now fire weapons

5. Settings General added Toggle Chat option with a configurable hotkey

6. PVP Battlescape fixed issue where the other player could see unit arrows when holding Alt

7. Minor fixes and polish

OpenXcom Co-op Mod v1.28.0 – Beta Release

OpenXcom Coop Mod 1.28.0 (OXCE 7.15.0) 

Changelog 2025/10/05

1. Battlescape Improved unit death synchronization

2. Campaign PvP supported

3. Campaign Both players control UFOs AI controls XCOM units

4. Minor fixes and polish

Status
Public beta. Playable but WIP.
Open source code will be published on GitHub in October.

What’s included

Campaign synchronization

Battlescape synchronization

Shared bases, items and research

PvP

PvE

Custom Battle mode

Quick install (Windows)

1. Buy either UFO Defense or Terror From the Deep on GOG, Steam, etc.

2. Go to Openxcom.org and install OpenXcom Extended.

3. Test that OpenXcom Extended works by launching the game.

4. Copy all files from this folder to the main game directory (where OpenXcomExtended is installed).

5. Make sure read and write permissions are allowed for this folder: "C:\Users<user>\Documents\OpenXcom".

6. Make sure you’re running OpenXcomCoop.exe as an administrator.

7. Launch OpenXcomCoop.exe

8. Done!

More information about the features and how to use the mod

https://www.moddb.com/mods/openxcom-coop-mod/news/development-status-of-openxcom-coop-mod

UFO Defense gameplay video: Youtube.com

Terror from the Deep gameplay video (1 hour): Youtube.com

Best regards,

Xcom Co-op Team

Full Changelog: xcom...xcom