what pokemon booster packs have the most valuable cards expensive Box of all time, #pokemon The Most Valuable Base Set

Blake's article on the Lost Legends promotion has a full list of the cards from the original Legends set that can be opened inside

I think the lack of ability text helps it

"In 1998, only 39 copies of this card--designed by Atsuko Nishida, the original creator of Pikachu--were awarded to winners of a Pokemon illustration contest

Umbreon secures its place as one of the most beloved figures in Pokemon with this new "Moonbreon," occasionally called "Sunbreon" to differentiate it from its Evolving Skies twin

The visual tell: distinct artwork you recognize as different from the card you know, with a standard border (unlike the borderless Secret Rare)