If you have played The Witcher 3: Wild Hunt, you know about Gwent, the card game within the game. CD Projekt RED has included the decks in the Limited Editions for expansion Hearts of Stone and Blood and Wine, and players could get the physical decks as well with proof of purchase. But that will soon be coming to an end.
The Witcher Store has said in a recent FAQ that it wants to stop sending out the physical decks on June 10, as long as supplies last. Players can still generate a code that will get them the Scoia’tael, Monster, Nilfgaard and Northern Realms decks. but "having a code does not guarantee a purchase," the site said. "Remember, it’s 'first come, first served'."
If you didn't get the limited version of the expansions, you can still buy the decks for $10 each. Of course, if you have never tried the game, then you will want to learn how to play it so you can crush your opponents.