- There is a hard cap on resource generation that can only be increased with Commerce research. Mousing over the production chart will tell you how efficient you are with your production. You can hit the cap, even with maxed research, fairly easily with very few cities.
- The more buildings in a city, the more health it has, so it can be worth it to build buildings you may not directly need if you think those cities will be in danger.
- Scout towers upgrade into Anti-Air once you hit the Modern Age. They also get more expensive.
- Science research makes ALL other research cheaper, including unit upgrades and other library tracks.
- You can make a production building repeat its queue infinitely by hitting Q.
- Money income is directly related to the number of cities you have as well as the amount of territory you control. Territory income can be boosted via the temple building.
- Each city can only have one Wonder, but you can have multiple Wonders in your nation. An early good one is the Terracotta Army, as it will constantly stream out basic infantry for free, letting you do a lot of early scouting and harassment for very little investment. Note that it slows down its own production speed the more units you have.
- In Conquer the World games, Wonders won't activate their benefits until you have 4 Civic research unless the wonder is in the map you're fighting on.