Only the second wave of 8 star wars figures (greedo hammerhead walrusman power driod luke x wing death star droid r5-d4 snaggletooth) were released on 20-backs.
Newest run is Chewbacca with a 12a, 12b, 41a, 45a, 45b, 45c, 65d, 70b & 70c. Missing a 30b which is known to exist as MOC. Possible existence 41b & 41c.
Total unique palitoy cardback variations collected: 404