There are about 33 missions. The big part of the missions have a few variants, which depends on the earlier choices. Moreover you don't play all the missions during the one campaing. There are two possible endings of the campaign and many smaller plot choices. The next thing are city/road cards, which can be different during each game. There are a lot of road/city cards, which have the same "front description", but after you reverse it you can see something completely different.