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Consistently trades in the 15,000-20,000 range

That scarcity gap between retail and prize printings keeps prices high

Though there are more types of double faced cards and other rules mostly to do with various other keywords and the way they can affect the handling of double faced cards the above will cover you for learning how to incorporate cards in your deck, along with the basics of how they work

Understanding Pokemon Card Rarity symbols can be complicated, not only because Nintendo have never seemed to explain it efficiently, but because theres a handful of symbols to understand and it can get confusing