Other's have already explained what I was thinking. That Shikamaru gives himself a debilitating poison, when it starts affecting both him and Hidan, he hits himself with the antidote, then does stuff to a still crippled Hidan.
Quote Originally Posted by ASSpirine
I hope Kakashi somehow gave some blood of Kakuzu or one of those mask thingies to Shikamaru and he pretends he's hit. Meaning Hidan kills something else instead.
That would be pretty badass except...does Kakuzu even have blood? He just seems to be full of sgwiggly black things. And the mask thingies I'm almost certain don't have blood.