Deathstroke

Slade Wilson, aka Deathstroke, the world's greatest assassin is possibly the deadliest hand to hand physical fighter that Batman has ever faced. With the ability to use up to 90% of his brain, he is a tactical genius that can think nine times faster than the average man. Armed with a titanium katana, dual pistols, several grenades and an assembling rifle there's nothing he won't do for money or for a chance at vengeance.