When you counter a spell on the stack, it has no effect and goes straight to the graveyard
Its a little more than what youd expect from this completely one-note character, but Sarkhan knows what he wants to be
Copying an X-cost spell will also copy the value of X you paid into the original
The basic problem is that the finisher for the deck used to be infinite mana into lots of draw and something like a Comet Storm with counterspell backup
Choco, Seeker of Paradise I expect Choco, Seeker of Paradise to overtake Kastral, the Windcrested as the games premiere bird commander on the basis of color alone: Green is the best color for casual EDH decks, and adding it here makes Choco decks much stronger
Still, I believe that Expressive Iteration actually has deck building restrictions to it, being almost non-abusable in combo decks and holds up a much lower ceiling in Control decks