Will the units and goods for negotiation change, when I move up in ages?
Yes! The units' age and the overall difficulty of the encounters depend on your own advancement in the tech tree when the expedition begins. You may also face two-wave battles, as well as units with boosted attack/defense depending on your own era.
The same applies to the negotiation option. You will have to guess a random combination out of 3 - 10 goods from the current era or the era below, depending on difficulty. That said, as you advance through the ages, the goods required will be changed as well.
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