The other cards you will use to complete puzzles, which will in turn give you a prize. Here is the puzzle/prize directory:
Sculpture Puzzle - Achilles' Heel
Drawing Puzzle - Harmony Pack
Music Puzzle - 5x Diamonds
Painting Puzzle - Titan's Challenge
Theater Puzzle - Morpheus' Arms
Literature Puzzle - Papryus' Privlidge (gives you a Plutos Parchment every day for 20 days if you logged on the previous day)
Cinema Puzzle - The Fifth Element!!! ;)
If you complete these you'll get one of the Wind Devines, Apeliotes.
I opened my three cards as soon as I logged on - I got 50 Turnips, 10 Diamonds, and an Apollo's Lyre.
I hope I can win that Devine!
EDIT: I HAVE BEEN TRYING TO WIN MORE CARDS BY WINNING COMPETITIONS BUT WHEN I WIN THEM I NEVER GET THE CARDS.... IF YOU'RE HAVING THIS ISSUE THEM COMMENT OR PM ME!