The Cell space on the Dungeon Board says: " Lose 1 Follower. You must leave one of your Followers in the Cell. If there are any Followers already here, you may take one of them with you."
Now do you always leave a Follower on the Cell space no matter what or only when it's empty? The way it reads it seems like you have to leave a Follower every time you land on the space but can also take one if there's any already there. So which is it?