We know that there's a time limitation (90s) each turn in Hearthstone in order to keep each game staying in a reasonable playing time. However, sometimes, it can take ridiculously long when you have a crazy setting up.
YouTube user The Optimistic Brit has recorded a video on how this happens. He and his friend set up a battle using a combo with two cards: Knife Juggler (deal 1 damage to a random enemy when you summon a new minion on board) + Dreadsteeds, one of the new cards from the latest Hearthstone expansion The Grand Tournament, which only has 1 HP but can respawns when dead. The Priest buffed Knife Juggler heavily and then use Faceless Manipulator to copy another one along with the 5 Dreadsteeds, the board can go crazily with the endless 1 damage and the constantly showing Dreadsteeds animation.