Kuro
Kuro is the former Captain of the Black Cat Pirates. He is known as "Kuro of the Thousand Plans" for his elaborate plans that virtually never fail. Thusly, he earns the title of the second most intelligent person in the East Blue behind Ben Beckman. He has super-human speed with which to deliver his attacks. His skill is such that at full speed he is only able to be seen as a vague blur or by the damage his attacks cause. He primarily uses a special attack called Shakushi (Death Scoop/Death Ladle), that allows him to sweep a large area, killing anything his claws connect with at random, including his own crew. The technique travels roughly the same speed as CP9's Soru ability. The difference is that when Kuro uses that technique, he cannot see what he is attacking, whereas CP9 have mastered this ability and therefore can. (Source: Wikipedia)