I used face value and calculated minimum extra value based on the $0.10 price point. Lets not forget each pack purchased from the official Splinterlands site will have a chance at the ongoing milestone airdrops. Packs being cheaper 1 vs. 1 on secondary markets for actively sold packs is the norm. One isn't going to go to secondary markets to pay over the amount Splinterlands sell them for. Look at it this way; two days ago if you purchased one pack you got one pack and a chance at an airdrop. If you purchase a pack during this special event sale you get one pack, a promo card and a chance at an airdrop. No matter how you dice it, purchasers are getting more for their purchase during the sale.