In addition to collecting, booster packs are used to build decks for playing the Pokmon TCG
However, in the official update on X mentioned above, The Pokemon Company does say this selection of cards will expand over time

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Valley Dasher seems like a great two-drop for any aggressive deck and Im surprised it hasnt gotten more attention
See the storage guide Buying the single is the sane path for a master set, given how long the pull odds run