No, the drop rates are 1-5%. It took me 4 days to win Spring Shehera. I'm farming Ninja Spy every day for Spring Rumiko. Just keep going at it until they drop.
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"yeah, there are extra missions, believe 2?"
14 dailies with 12 required for the prize. Final tally 14/12 if you do all of them. I'm already at 14/12 when the 14th daily hasn't been offered yet. I will finish the event with a tally of 15/12.