All right, so despite my earlier bad luck I've managed to get 8 copies in total, and already have -2 cost and +2 to skill level. I'm optimistic about having a decent Fallen Angel once this is done. Although, I'll need a lot of Platinum spirits...

The good thing about the drop rates is that, when I switch windows and come back to find I've lost a match (it's rather erratic as to whether it pauses the game or not when I do that), I can say I didn't lose too much...