Answer

Exceeding the point limit

Your score at the end of the game is capped at the point limit of your game. So in a game to 15 points there is no gain in going to 17 points.

However, it does matter how many points your opponents have. So taking away points from them will get you more ranking points. This can be done by taking their 'soft' points. Soft points are: Trading route, Biggest army, Merchant, Metropolis.

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