Below is an oversized promotional Eighth Edition Two-Headed Dragon card given away at E-3 (Electronic Entertainment Exposition) last weekend. The card features the normal card front for Eighth (with a black border, which the Eighth premium cards will have), and an enlarged version of the card art on the back.
Similar promotional cards that preview Eighth Edition will be given away at other events this summer, including Origins, GenCon, and the San Diego ComiCon.
Card front (approx. actual size)
Card back (approx. actual size)