The early Pokemon sets include Base Set, Jungle, and Fossil, which were instant hits and now contain valuable cards such as Charizard (Base Set), Pikachu (Jungle), and Gengar (Fossil)
This means that the best way to take advantage of cards like Cavern of Souls and Delighted Halfling is to simply play powerful creatures
I would happily volunteer to help playtest, but I don't have any sort of group to test with right now
Specialist auction houses can help identify rare cards, attract serious collectors, and achieve competitive market prices
Affinity is a powerful ability, and with your lands counting along with most of the rest of your permanents most players reading this can readily remember how easy it is to turn seven into a far more reasonable number