I love both versions of this art but let's take another look at the promo version of the card. First off, here's the initial sketch that Mark Winters turned in.
Pain Seer (Game Day Promo sketch) | Art by Mark Winters
What immediately popped out at me is that there are legs hanging in the art, something that was subtle enough that I didn't realize it when I looked at it. I also love seeing what the tools of the trade are for a pain seer. When it comes to the final piece it's largely the same concept with just a few things changed to clean up and simplify the piece.
Pain Seer (Game Day Promo) | Art by Mark Winters