Your economy is the center and most important aspect of your game in Polytopia. You increase your income by upgrading cities. Upgrading a city increases the income the city provides by 1, allows you to train one more unit in that city, and grants you a choice between two bonuses. In nearly all cases, do not partially upgrade cities! Doing so grants no benefits to you. Keep the stars instead, as that keeps options open. However, if you want to upgrade your city soon and are afraid that enemies will step on your resources, preventing you from using them, then you can harvest those resources immediately. Build buildings in places that keep options open. For example, try not to block CH or Forge spots with Lumber Huts. Do not build things over harvestable resources (unless you need the two stars that turn), e.g., do not build a port over fish without harvesting the fish first. Do not buy too much tech early-game. Do not buy techs that you will not need to use. However, if you are about to conquer villages/cities and you know that you will need to use a tech soon (e.g., Sailing/Navigation), purchase the tech before capturing the village/city. Tech costs rise for every city you rule (+1/city for T1 techs, +2/city for T2 techs, and +3/city for T3 techs). If it is too late to buy tech cheap, consider getting Philosophy which reduces all tech costs by 20%. Grow Forest → Burn Forest → Farm is almost always a bad deal if you are not using Windmills. At 15 stars for 2 pop or 7.5 stars/pop, it is the worst in the game (besides temples, but those are typically built for points, not population). Even Ports are better, at 5 stars/pop. However, Grow → Burn → Farm next to a Windmill is okay, at 5 stars/pop once the Windmill is built. But keep in mind that if you have open shallow water tiles, Ports still maintain a slight edge since you do not need to pay for a Windmill.
