Price drops are normal at launch, but the dip from Aftermath cards on the secondary market went beyond the typical decrease of individual singles prices following an MTG sets launch
You need to have a functional Remote Duel setup and any tournament supplies you will need, such as a tournament legal Advanced Deck, paper and pen to track Life Points, dice or counters for card effects, extra sleeves to replace any that become damaged, and so forth
I prefer the Lagoon (Teal), Eucalyptus (Sage Green), and Snow (White)
However, back in the early days of Pokmon, during the Wizards of the Coast era, some designs made their way into print that would later be removed
You can find collectors online through social media such as Facebook and Instagram
But what of the nascent tribe that our Ox of Agonies will stand atop