Total War: ROME II Patch 12 is now live and should be automatically downloading to your Steam client as we speak (please give it an hour or so to roll out to all of the Steam servers if it is not downloading yet).
This patch will bring some improvements to campaign and battle AI, as well as some balance changes and general improvement to your game.
Please be sure to disable mods, verify your steam cache and try a new campaign to see the full effect of the patch.
Note that mods that have not been updated by their creators are likely to become incompatible with the update, so please disable them until they are updated. If you are having issues since the patch, please visit our support forums below.