So right now Nintendo has a deal where you can play the Switch version of Overwatch free through the week if you have a subscription to Nintendo Switch Online. I found out by accident that if you download the game and go into the settings, you can link it to your Blizzard account and redeem the "digital goodies" that you could normally only get by buying the game, including the Overwatch cardback for Hearthstone. Just thought I'd throw this out there for anyone who might want the cardback without having to buy the full game.