by chademe
Regarding the 2nd question, you're not allowed to abandon territories once they're yours. It doesn't matter how you acquired them, you must always leave at least one unit there.For the 1st question I can't help you much since I only play with my family. I would think a somewhat consistent group would be better. New people coming in at game 7 for example might be at a slight disadvantage because players who have been around the whole time have been able to modify the board to their advantage.
