I was getting incredibly annoyed with this boss. Sometimes though when you are stuck on a boss the best thing you can do is create the largest thing possible in a couple turns and hope they don’t have any convenient removal spells. In particular I loathe the “Destroy Target Creature that has taken Damage.” It always comes at the worst possible moment for me in these campaigns.
That said, I’ve finished the third wing of the raid and am now just waiting on the last one. So that’s a nice bit of progress.