I'm working on constructing some type of metal/dark deck. Now I'm not sure which type of packs to buy? I enjoy playing Pokemon TCGO so B/W packs are nice, as you get codes but I'm not aware of too many useful dark or metal cards in the series right now. So which packs from HGSS would have the best chance to contain the cards I need. (I'm really hoping to be able to build a deck Tyranitar Prime)