One Piece has alot of strong guys. For the strongest, there's only a few characters. But who is the scariest? You don't have to be the strongest to be the scariest. Furthermore despite the anime adding unneccessary fillers they can definately make characters scary.
So who is the scariest? Hody may have been weak but the anime really made him scary. Doflamingo is downright pyshcotic.
Give your thoughts. Also note that just because a character isn't strong doesn't meant that he isn't scare.