0.444 per cent chance: 0.222 per cent per card (5th card probability rate, regular pack) Rainbow Full Art Zapdos EX, Rainbow Full Art Wigglytuff EX (Pikachu Pack) 0.1 per cent chance: 0.05 per cent per card (4th card, regular pack)
In practice, this doesnt seem to be much of an issue due to the redundancy built into the deck, and it works out that the decks fail rate of losing to itself due to mulliganing into oblivion is not much worse than the Legacy version
While Deoxys' other rival, Jirachi, boasts a roster of valuable cards, neither Pokemon can compare to the sky-high prices Rayquaza's best cards can reach
This is chaotic, as you can get practically any spell from your deck, be it one of the biggest, baddest of the Eldrazi titans or a Llanowar Elves