Talk:Spring 2017 Event/@comment-31903190-20170520051704/@comment-26082284-20170520080015

Well, it's (probably) not wrong number, but you need to take couple of things into consideration.

First, it's compound from droprates for S and A rank, but your proportion of A to S ranks might be different than what it was for all poi reports. If you are getting mostly A ranks, then your droprate will be closer to 1.3%...

Second, it's still just a percentage chance. They won't add up, but every single sortie is just another chance with fixed probability. So even with all S-ranks after 50 sorties you'll only get cumulative drop chance of about 80%. So out of every 10 TTKs 2 still won't get Kamoi even after 50 consecutive S-ranks on E3E.

Probability's a bitch.