I generall find that it is better to use one card until you get to angel as for me it has ended up being MUCH cheaper and less time and effort to get soo many of the same cards, going from angel to archangel and beyond i'd use 3 cards max as failing on 3 cards multiple is unliklier than it failing on 1 card multiple times ... this is just my strategy and works fine for me, maybe not so much for others