FOLLOWING - Imperian Online Help
You cannot follow anything but a player in Imperian because of the fundamental nature of player movement. We do not actually like the idea of automatically following something else, as we feel it is a little bit silly. Mobiles move relatively slowly, and thus it's reasonable for you to simply move when and where they move. Players, on the other hand, can move far too fast for you to follow them that way, which is why one can automatically follow players, but not mobiles.