User blog comment:Xilinoc/Ch. 685 - THE PERFECT END/@comment-24574959-20160817141812/@comment-28044177-20160818054207

Aizen fused with his Zanpakutou. So all you have to is see Aizen himself right when he releases Kyouka Suigetsu's power in order for you to be affected. He did it as soon as Yhwach came out of the portal and saw Aizen.