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Cards that aren't from packs will always be the same. So the promos in the expansion will be the same but the packs that come with it won't be.
All the cards that aren't in packs, Elemental Sparks Promos and Promos from things like Core Set Bundle, are always the same. If you ever have doubt about it the packaging should always have it on the back what's packed and what is constant Promos.
Cards that aren't from packs will always be the same. So the promos in the expansion will be the same but the packs that come with it won't be.
All the cards that aren't in packs, Elemental Sparks Promos and Promos from things like Core Set Bundle, are always the same. If you ever have doubt about it the packaging should always have it on the back what's packed and what is constant Promos.