Well, it's a simple idea: Let us create card sets for our characters. So if I want to play a lvl 15 campaign map because it has fairy on it and I know which set is good in this map, I just have to click on the card set I have created and my character gets equipped with all the items that are available. If one item from this set is equipped on another character and you dont have a spare one, this itemslot wont get equipped (stays empty) but the rest will. This way we dont have to un- and requip our characters over and over again.