Phantom Trade

Send 1 "Phantom Knights" Spell/Trap Card from you hand to the Graveyard and add 1 "The Phantom Knights" monster from your Graveyard to your hand. This Skill can only be used if you begin the Duel with a Deck (excluding Extra Deck) that includes at least 1 monster and contains no monsters other than "The Phantom Knights" monsters. This Skill can only be used once per Duel.