Turin, the five cards that are selected are for each spin. On the first spin, five cards are picked. On the second spin, five more cards are picked. On the third turn, five MORE cards are selected. So, of course it looks like there are more than five cards. =/ Though, adding more of a single copy would increase the chances of winning one.
As for the best farming decks, I'd have to say Nihilus and Evil Hamster have the best ones so far. I keep fighting piekotwo, but I never win anything. >.<"
And @ Dragoon, yes, that is his name, I believe. I faced him just last night.