Gwent's official esports series.
Gwent Masters is the name of Gwent’s official esports series consisting of CD Projekt Red-organised tournaments, i.e. Gwent Open, Gwent Challenger, and Gwent World Masters, as well as licensed and community tournaments.
Gwent Masters tournaments are all held in best-of-5 Conquest formats, in which each player is expected to bring four different decks from four different factions and one deck per round is banned, i.e. the player is not allowed to select it for play during that tournament round. For additional information see here.