Fun times! Blizzard has brought back a Hearthstone Tavern Brawl event from November that features two players battling one AI opponent — Mechazod. It’s a hastily crafted form of co-op, in that the UI is basically the same and there’s no added quality of life features, but the functionality is there, and it works.
I really hope Blizzard implements this gametype down the line. I would easily replay every adventure again on Heroic mode just to storm through them with a friend. Of course, if this is coming, the Blizz is probably taking its time with it and ensuring that it’s perfect.