I can excuse the changes in Co-Op mode, but I have a few concerns with the Dungeons. First, the bosses are incredibly difficult to kill, even with upgraded legendary cards. Next, there are levels where you have to face 2 bosses, despite indicating only one (ex. The final boss of Chapter 3 Floor 7 is Bedlam but an additional Warlock is present). Third, the limited amount of keys. Given how difficult the levels are, the least you can do is give us unlimited chances and not have us wait for hours.