I ran a few times into the Polyhymnia and lost every time. It was really a punishment and there was nothing I could do with my deck. The Celestial Stag can be annoying but is not op in my opinion. I lost once very hard because of this card, but could also kill it many times pretty quick.
I agree with the nerf on some cards, since they did this in the past. It's part of the game and is needed for the balance. Other card game did it multiple times too.

!PIZZA