User blog comment:Xilinoc/Ch. 596 - Rubb-Dolls 3/@comment-5693502-20140910133132/@comment-117598-20140910213451

If Mayuri arrived when Ikkaku and Yumi were fighting Bambietta, when did he go back to his lab to create the drug if that was the first time he saw Giselle's ability? He didn't create it right then and there. That means he arrived on the battlefield with the drug in his pocket already.