According to a new update on Play! Pokemon’s Regionals page, Dragon Vault will not be legal for Regionals. This is because the blister packs will be released gradually across the United States, which means it wouldn’t be fair for some players to use the cards in their decks when other players have no way of purchasing them. The mini-set’s official release date is “October,” but some distributors are claiming it could hit store shelves as early as next Friday. Dragon Vault will be legal for Modified tournament play starting October 15th (all Regionals will be held on October 13th).
However, as per TPCi tournament rules, Rayquaza from Dragon Vault will be allowed in decks since it’s just a reprint of the one from Dragons Exalted (EXP. Share and Super Rod are also reprinted in Dragon Vault and will also be allowed, but no one really cares about them). So if you can find the Dragon Vault packs before Regionals and need the powerful Rayquaza in your deck, you’ll have a much easier time obtaining the card (and without paying the ridiculous prices the shiny one from Dragons Exalted is going for now).