Blizzard has released a patch for the Hearthstone exploit that allowed players to replicate cards and skip their opponent’s turn.
The exploit used a combination of cards to lock the opposing player out of their turn. This was effectively done by creating so many animations that the player’s turn would run out watching them before any moves could be made.
Recent patch notes reveal that one of the cards responsible, Shadow Visions, has been updated so it can no longer replicate itself or create spells in an empty deck. This should render the exploit unavailable.