Board Thread:General Discussion/@comment-5996974-20140820090112/@comment-8986886-20140820103855

That drug sure is convenient. Mayuri can't be killed by Hitsugaya, and after some time Hitsugaya is rendered helpless for 30 seconds. Do you suppose he was exposed to the drug when he fought Chuhlhourne? He was the only zombie Arrancar who didn't feel pain when he was zapped by Mayuri, a (sure?) sign that he'd been given one of Mayuri's experimental drugs. I believe Mayuri used a drug on himself to improve his reflexes, to be able to fend off Hitsugaya's attacks. He may also have given the other zombie Arrancar a selection of experimental drugs, such as superhuman strength, knowledge, and bravery, which Mayuri has mentioned.

On a side note: I guess Kubo isn't exactly hard pressed to finish the arc quickly. If anything he's delaying the plot just as he did in the chapters with Guenael, The Vanishing Point (created by Gremmy's imagination). Back then Isane and Yachiru forgot that the enemy even existed over and over again, and now Hitsugaya is caught in a time loop. I'm telling you we'll never see the end of this arc... ^^