User blog comment:Xilinoc/Ch. 590 - Marching Out the ZOMBIES/@comment-6657474-20140724020435/@comment-14244059-20140724230451

I'm fairly certainly Mayuri was just using his "benevolence" as an excuse for bringing out his Arrancar zombie-experiment... things. As far as we know, these things have never seen combat and what kind of creator doesn't want to see his creations in action?