Re: One Piece 662
I wonder if the reason Law takes the hearts is to force people to obey him? It looks like he preserves them by freezing them right? We've also seen that people can still feel the rest of their body even if it's separated since that samurai could sense the other half of his body fighting brook. This brings me to my point. If normal damage still applies to separated body parts, then wouldn't simply crushing a persons heart kill them instantly.
I can't think of a better way of forcing someone into obedience then by literally holding their heart in the palm of your hand. So perhaps when Law sent 100 hearts to the Marines, it wasn't to show that he had killed them, but rather to show that he had gained 100 note-worthy pirates under his control, which if given a shichibukai status would mean them being under the Marines control as well. No wonder the marines accepted him. They really couldn't risk leaving him unchecked. If he ever got hold of one of the Yonko's hearts, he'd instantly become a major power overnight, and the marines couldn't risk having that.