So this just happened
I had whirlwind + armorsmith, he had mirror image + mirror entity.
He wound up with nothing but mirror images in hand so couldn't attack except with hero power and the last armorsmith he mirror entitied. The maths just weren't on his side.
I didn't do the math but I
think if he had kept going the game would have hit the turn limit and ended in a draw. He wound up conceding a few turns after I took this.