yugioh card box Yu-Gi-Oh! TCG: 25th Anniversary Rarity Collection Booster Box, KON86328, Black : Toys & Games like you’ve never seen before Yu-Gi-Oh! cards Crossover Breakers Booster

That's what's being focused on in the battle

While noticeable exceptions do exist, such as the phenomenally rare and valuable Umbreon Star POP Series 5, among the ungraded Umbreon cards currently moving on the secondary card market, this one is king

The Shiny Vault bonus sheet from this expansion was so popular that the Pokemon TCG went back to that well as recently as 2024 with the Paldean Fates expansion, which also featured a subset of shiny Pokemon cards

This was clearly a test of the concept of serialized cards in Magic, but to my knowledge, their existence has never been officially acknowledged by anyone at Wizards