You know that there was a problem in Order & Chaos Duels when players were using alchemy and they lost their cards. Now, the cards are being returned. If this happened to you and you are an iOS user, here is how to get your cards back:
1. You will need to update your Order & Chaos Duels to the latest 1.7.1 version.
2. If your game is already updated but your cards are not returned, you will have to contact the Customer Care using the menu you will find in the game.