The post above made me think about the need for cities in civ. Why wouldn't it be possible to have one or more civs that don't create cities by default. a) But rather spawn units just like the barbarians do. With the same ability to capture cities but at a bigger cost then civs with cities. b) With temporary moving cities, that are formed by caravans. Also with the ability to attack and take over cities. A bit like the Tuareg people who have recently illustrated this by taking over some cities in Mali.