It really depends on what the deck is, is it in good condition? Are the cards in the deck good? Is it worth it to trade your black winged dragon? Do you like your that card that much? I can't claim to be in your position but you should take these things into consideration before making a decision... to me one card for an entire deck seems pretty sketchy but as I said I'm not in your position, for all I know it could be a good deal... but in the end only you can only do what you think is right Apparently it is...