Kenner released three Star Wars “Three Pack” sets in 1978. This is the Villain set which includes a Stormtrooper, Darth Vader and a Death Squad Commander. It has the long play logo and white price sticker area at the top right corner that the original 12-back cards also have.
The card back shows all three trio sets from Kenner. They include the Villain set, Hero set, and Android set.
These trio sets are very rare a sell for quite a bit when they are available. In March of 2012 one of these sets sold for $2950.00. More recently in June of 2013 an ungraded set in very nice condition sold for $3729.00. This is very close to the same price a Hero set sold for around the same time. That set sold for $3718.00 and was graded AFA 85. Obviously, if you need one of these for your collection you may have a difficult time finding one. Still, they are not likely to lose value and more likely will escalate in value even more over time.
These sets were later re-issued by Hasbro and sold exclusively in target stores around 2012.