The thing that people have had the hardest time grasping here is that creatures attack the other player, and can not attack the other players creatures. The Hearthstone way seems intuitive.
I love the art and the flavor on Elesh Norn, but I hate how she plays when she can be powered out early, there is no way to around her, since all your guys are now dead.
Mark Poole is the only acceptable counterspell art. Screw Jace.
Tempest and Ice Age is ok as well. And Masques. I love the art in masques. The promo counterspell with the looks all Mirage-y is nice as well.
I second Ashling, I love that card. I tried thrashing wumpus without really having a theme where it fit in and it didn't do well, surprise surprise. I'll be happy if you get it to work.