A Call To Arms is a technology that is researched from a Level 2 or higher Foundry. It provides a damage bonus of 3% per level for all Units and Structures in the Local group when your town is under attack, and does not stack when researched in multiple Foundries. In order to benefit from the damage bonus, the town must have a certain amount of idle laborers depending on the technologies level (starting at 60 idle laborers for level 1).

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