I got 3 Mighty Knights: Zombie Management
@developers: screenshot is available if you don't already know about this. Let me know and I can mail it in.
My 3rd mighty knight magically appeared when I played an Intrigue on another player. It appeared on one of my trade routes in a spot which never had a knight on it. It can't be activated with a wheat, it just sits there eating the brains of some poor Catanian farmer.