User blog comment:Codgod13/Round 7: Mayuri Kurotsuchi vs Alex Mercer/@comment-1017446-20110517005254/@comment-3528601-20110517110730

so Mercer can withstand a sword to the head. Plus his weakness has shown to be poisons and Mayuri is an expert in that. His bankai mist will dissolve an kill mercer almost instantly, and Mayuri has the only antidote, its impossible to build up antibodies, the only way to repel it is with large amounts of spiritual pressure wich mercer has none of. anyway, mercer isn't a soul reaper, so he might not be able to see mayuri in the first place, chameleon abilities aside.