shiny treasures booster box card list Treasure Each booster box contains 10 booster packs Shiny Treasures [JP] – Sakuras

In the set there are: 10 Showcase uncommon cards 14 Showcase rare cards 6 Showcase mythic rare cards 2 Borderless planeswalker mythic rare cards (see below) In Draft Boosters, whenever an uncommon, rare, or mythic rare appears, if it has a showcase treatment that treatment will appear roughly one out of four times

Lets go to Star City Games and search for the cards

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no clue how it balances (my gut says it's broken, but I don't know what that Level restriction would mean in practice)