Well, the if we look at the 25 most pricey rares from the set (of 54), we note that the pre-reprint cost of that basket of cards was close to $596, or an average of about $24
I havent covered every matchup out there, but as you can extrapolate, in general, Roaring Moon ex struggles against one-Prize decks because it doesnt have any good option: dealing 220 damage with a two-Prizer, sacrificing a Stadium, is not a good way to fight Cramorant or Gardevoir
Rarity is a rough measure of how likely a card is to appear in a booster pack
2 The journey continues
Proliferate, graveyard matters, +1/+1 counters, mill, and self-mill all became angles we could design new cards around as well as find reprints for