Finding this one was a tough process.. Well maybe for you it would be
easy. First go to the Fifth or Sixth Floor in the castle(or maybe the
dungeons) Then look around the the place until you find a room with two
or more people there. go to the back of the room and you will see Chests
(not the hairy type of Chests just Treasure Chests) go to the one you
want to open. BUT BEWARE! you need the cards on the side of your Folio
Universities like Merelin,Morgan le fay,some guy who made the snitch,
Godric Gryiffindor(I don't have him yet) and some others that I
forgot...OH and you have to have this KEY icon next to the card in th
folder. I unlocked most of them Even got the divinitation tea leaves
mini game :)