Shepherdess
c4tsitoro The Sheperdess doesn't seem like much, but she is a very popular hero. A mid-level Shepherdess alone can make a person completely immune to pillage attempts because of the vast amount of sheep that are created. It doesn't take any active actions (unlike Total Newbie Handbooks for instance) and sheep are such low net power that even if you have hundreds of thousands of them, if you lose them all in seiges/regulars it's not likely to cost you land.