The simplest logic: backed by R card. For example, the cards of 1 Yuan Classic Edition, 2 yuan Deluxe Edition and 5 yuan Legend Edition are all equipped with 7 R cards+1 other cards. This other grade card is most likely SR card, SSR card with a small probability, and other rarer grade cards with a smaller probability.
At present, there are more than 20 card grades on sale, some of which are very clear in rarity and rules, such as R, s R, SSR, some card grades that must be issued when opening a specific card package, and cards with different card faces and rarity but the same grade name in different packages?