This is first released DLC for Cossacks 3 and it adds Polish campaign to the game. This campaign is amazing and its final mission is based on famous Battle of Vienna in 1683. I can say that basically all the DLCs campaign are often better structured and balanced that original campaigns, so, I absolutely recommend playing them all. And if you will decide to do it, you can go with the chronological order of DLC releases indeed starting with Days of Brilliance.
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