You collect Cards during the Collection event.

• Cards are obtained in cases, which you get by participating in events and through other achievements in the game.
• You can also get the card you need by exchanging a Joker for it, if you happen to get one.
• All your cards are grouped into sets, which you can track on the Collection screen.
• Each card has a rating that shows its rarity.
• Sometimes you will get duplicate cards. These are automatically converted into tokens, which can bring you additional rewards.