I read in the rules page under construction; ?Have at least one Builder NPC at your location (maximum of 10)?. What does that mean? Is that per facility, or per city? Or is that the most a single player can ?lead?? I would think that if you had quite a few (over 10) you could put them to work on a city, get it done fairly quickly.
10 is the maximum you can use on a single building. I think 12 is the maximum party size. So if you drop groups of 10 everywhere you're going to start constructing buildings, you can go around to each group and set them off. You don't need them in your party to put them on a construction task.
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"May the Grace of Ara go with you, and His Vengeance be wrought upon your enemies."