This post concerns the Mac and Linux versions of Empire: Total War, ported by Feral Interactive.

We have updated the Mac OS X and Linux/SteamOS versions of Empire: Total War so that both versions now use a platform-agnostic maths library. This modification allows Mac OS X and Linux gamers to play against each other, both online and on LAN. Previously, this was impossible because the original library would work differently on different platforms, causing the game to be unable to keep in sync across platforms.

The changes to the maths library are fairly complex, so we are offering this as an opt-in Beta option so that you can try it out, and then report any issues you find back to us. We can then make improvements before we make the update available to everyone on the main retail branch.

You can find the Multiplayer Beta in the Beta tab of the Empire: Total War Properties window in your Steam client. The Beta branch is called "mac_linux_mp_beta".

There are few important points to note about the Beta:

1. Battle replays created in the current retail version will not work in the Beta, as they are based on the old maths library. All your other saves and progress are fully compatible.
2. If you opt into the Beta you can only play against other Mac and Linux users who are also opted into the Beta.
3. The Windows version is not affected by this change, so Mac and Linux users will not be able to play against Windows users, even if they are opted into the Beta.
4. If you have issues, please email our support team so they can collate them and report back to our development teams for investigation. The email address for all feedback on this Beta is empiremultiplayer@feralinteractive.com
5. The Beta exhibits a known performance drop compared to retail builds on AMD cards running on Linux which we will be investigating.

We hope you enjoy the Beta, and look forward to your feedback.

Thanks,

The Feral Interactive Team