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Question about The “Age of Darkness” Expansion Caravel - How do you calculate the strength of the units in case of a Barbarian Attack if 2 Caravels and a trade ship are placed in a city?

Answer

The 2nd Caravel doesn't affect the trade ship. Therefore, 2 Caravels and 1 trade ship in a city only count as 4 units in case of a Barbarian Attack.