The introduction for Dragon Pokemon, Dragon Vault could not be bought in booster packs and was made in Dragon Vault Blisters. Each pack contained 5 holofoil cards, and they were released in October 2012. The set was a small special expansion with only 20 cards and 1 secret card.
Special cards in this set include Kyurem #21, Rayquaza #11 & Dratini #2.
Pokedex
Dragons Exalted
Boundaries Crossed 