4Squared

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 In any map that has resources connected to cities such as this one, you can gain an advantage using cargos instead of transports. Most would think cargos go in water. But they can move through cities and resources, carry more trucks and dozers reach farther for quicker expansion with a speed of 18 squares. In this map, using cargos, you should be able to claim all the gold mines in one corner by turn5.

4on4 Duel

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Best base placement for expansion is in the deserts, the corners. This would be considered a trick/tax map. Placing base last allows you to pick the corner closest to them, also they dont see your expansion until after its too late. Blue has finished turn1. White is still on turn0.