Board Thread:Questions and Answers/@comment-32610006-20170815210752/@comment-33728484-20170815212854

Some say that the drop rate of Stage 1 is 1%, but maybe they say so just because the drop rate is so low, I have no idea.

Anyway, I think I've done Stage 4 a little more than 100 times and I already have one Goku with 4 dupes at 100%, and another one at SA10. So I'm quite happy with the 15% drop rate, especially because on Stage 4 you get either the card or the medals, while Stage 1 is a complete waste of time.