I just added a Comment for the set regarding this, but thought I would check to see if others had more info. I believe all cards are available with either a thin/cream (like the scans for #22) or thicker/dark gray (like the scans for #25) cardstock, but have no idea why. Does anyone know if it's from two different production facilities or an early/later print run issue? Cream backs seem to be more common at roughly 4:1 in my experience. I've completed the cream back set and have 7 more to go to complete the darker backs. Should this be added as a variation for each card or parallel set?