So I did the first of my 15 Artist Proofs for the Iron Man 2 set. The cards are the standard 2 1/2 x 3 1/2", but they've a printed pattern on the back surface which means the media I'm using isn't going on the same manner as it does on the Strathmore bristol I'm using for my usual cards. The colours aren't absorbed in quite the same manner and there's a waxy or oily element to the ink that just resists colour as well, but I think I figured out how to get what I want out of them (one thing that seems to help is rubbing the surface a bit with a gritty eraser -- like sanding it, I guess).
I'm following the lead of a bunch of the other artists' on this set and not waiting for all the cards to be commissioned and just doing all of them since the deadline for getting these approved by Marvel looms.
I'm gonna post these one-a-day as usual, but I'm already quite a bit ahead and hoping to have all 15 done by this Friday.