Secret Rare

From BK2 onwards, Konami introduced Secret Rares to the game. These cards aren't playable but feature full art by Miura made specifically for the TCG. These Secret Rare cards have their own unique numbering and can appear in any pack BK2-5, so therefore are deemed their own set by collectors of the game. They exist in both Basic and Parallel/Holofoil. There are 28 cards by number or 56 including variant.