Before my last match, I replaced the only "Icecave Crasher" in my deck with "Drix Fatemaker" and clicked the "Done" button to start a new duel. In my opening hand, however, "Icecave Crasher" was back and remained for the rest of the match (a loss unfortunately ). Back in the menu, I checked to see if I had made a mistake by not dragging out the card I wanted to remove, but everything was exactly as it should be: "Icecave" out and "Drix" in. I’m playing on a MacBook via Steam. I’ve just uploaded the log (I hope it helps). Thanks for your attention.