Campaign
A campaign is a set of scenarios which should be won one by one so as to complete the campaign. In the table of records, there is a separate ranking for campaigns, and winning a scenario itself doesn't count in the table. There are campaigns which give the player an opportunity to choose the order in which some of the scenarios are being played (e.g. in the Unholy Alliance campaign, you may complete first four scenarios in any order as you like).
Some campaigns are available at start and can be played in any order. The other ones appear one by one after you finished the starting ones.
Important: The game tracks your progress through the campaigns via a save file, not a game flag. That means that you cannot play the scenarios in a random sequence. Start with the first scenario of one of the first three campaigns. When you finish that scenario, you create a save file. You should probably name that file by some appropriate name. Start the second scenario from that file. When you finish the second scenario, you save again. You should probably make a new file for this. When you complete the final scenario of the first campaign, save again. So far, so good. But when you start the second campaign, you MUST load your most recent save file first, otherwise your progress through the campaigns is lost. Continue through the campaigns with this method.
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