Gathering of Ghosts

Can only be used the turn you have activated "DNA Transplant". Return 1 "DARK" monster in your hand to your Deck and play 1 "Ally Salvo" from outside of your Deck. This Skill can only be used once per turn and twice per Duel, and only if you begin the Duel with a Deck/Extra Deck that contains no monsters other than Machine-Type monsters.