Tarot Cards are cards that tell the future, or in this case, past.
Role in Shrek
They appear in the deleted scene Fiona’s Prologue. In it, a fortune teller named Dama Fortuna narrates Fiona’s past, how she was born an ogre and locked in the tower because of it. After she finished, the cards float above the campfire and she draws them back in before putting them into her sleeve and Fiona approaches.