Two Blizzard developers used an internal game jam to try and make a virtual reality version of Hearthstone. In an interview with PowerUp, lead effects artists Hadidjah Chamberlain said that the project never made it very far, but had allowed players to explore the CCG's famous tavern.
Chamberlain said that the unnamed developers had "actually prototyped a VR version of Hearthstone" during Blizzard's annual Free Your Mind event. With only two weeks to work on the game, progress was limited, but players could lay down cards and wander around the Tavern before sitting down to a match with an opponent.
It sounds as though the developers hadn't really got an official version of Hearthstone running - players could set cards down on the table, but getting them to interact correctly with one another sounds much more complicated. They had, however, implemented an important new feature in providing struggling players the ability to flip the table if a match wasn't going their way. Not necessarily the most sporting way to play, but the perfect way to end a match when you know you're opponent is just toying with you.