>>26724544>>26723910If your store still has packs from Plasma Freeze, get those. The most expensive, playable card (Secret Rare Ultra Ball) is from that set. That set has an unusually high number of SR cards though, which is a bit of a pain.
What the other anon said about Phantom Forces isn't wrong, but buying boosters is fucking stupid for that set.
I'd also recommend Generations, since it's all reprints and getting it at a discount makes buying the sets worthwhile.
Oh, and if you can find pic related, buy it. Has reverse holo energy cards and staple trainers including a VS Seeker.