Nico Robin is indeed powerful which is why I must have her. I do not however, think she is quite as powerful as the darkness I now wield.

And just how do you intend to exploit those weaknesses if I never actually go near you? I don't have a legion for nothing you know, and I cannot fall into the ocean while I still have the abilities of flight. I see it is impossible for such a primitive being as yourself to know fear. Therefore it shall be all the more of a pleasure when I see your heart torn from your chest. If you resist it shall be a waste of your life.