>>532734236
They'll argue that older players would complain about having a high chance of pulling old ships on an event banner. It's also that SRs on rateup have a 2% chance and SRs *combined* have a 7% chance of dropping, so if you have more than 3 rateup SRs the math gets screwy (by which I mean, overly generous, and with no chance of off-banner SRs dropping).

>>532734768
It's a T3 material (see https://azurlane.koumakan.jp/wiki/The_Alchemist_and_the_Archipelago_of_Secrets#Alchemy ) and those require harvesting tools.