Re: defending coastline
 

The most common free fortresses seem to be the underwater nature ones. I don't think I've seen Firbolg Fortress as much in Dom3 as in Dom2... but that could just be bad luck

Re: defending coastline
 

I play the cradle map, and i use dominion to kill off sea nations early. another option is to build a fort and hope that you get another nation to attack it as well. as they siege the fort that will make the other 2 nations go to war.

Re: defending coastline
 

Xietor,
Your Idea is based on luck. I wouldn't trust it. Maybe if another nation was nearby, but in the early game its unlikely.