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However, as the game progresses, it becomes harder and harder to give advice. As an example, if your opponent builds three stables you should make a lot of pikemen to counter cavalry. But the number of strategies you can use at this point is so large that it's impossible to say that something is wrong to do. The later units become more gold-demanding (especially artillery), so an extra plantation is a good idea. Also, you should be exhausted for natural resources at this point, so if you still have villagers hunting half-across the map, pull them back and build a mill instead. If you're low on wood, consider some extra gold and use the market to buy wood. But it's not cost-effective, so only buy wood when you need it badly (for buildings or ships). With units, you should be able to find an alternative without a wood-cost. Be offensive with the placement of your fortress, but don't overreach yourself. If you can't back up your fortress with forces at a few moments notice you risk losing it. Remember that units not fighting are a waste and that upgrading units is more effective when you already have them. Likewise, don't upgrade units if you don't have any. Beyond the Fortress Age, the idea of the game is to basically keep producing troops and tech-ing up. Cards are your friends. Your card shipments are incredibly useful. Somethings such as forts and military units have to wait for there are many more useful shipments. Increasing your speed time of infantry and cavalry is very useful and needed. Make a deck that suits you but have many essential cards such as crates of wood, food, or coin or many improvements to give you an advantage against your opponent.
Try to respond to your opponents' building and counter his units. Try to macro up regardless. Get your fortress up as soon as possible. Do not feel limited by a population cap of 200.