If you could maintain excellent location, then the knuckleball. Unfortunately, that's the beauty of a knuckleball. There is no location. Even the pitcher does not know where a good knuckleball is going once he lets go.
Since that basically eliminates the knuckleball, I'll take the big bending curveball.
Yes doctor, I am sick.
Sick of those who are spineless.
Sick of those who feel self-entitled.
Sick of those who are hypocrites.
Yes doctor, an army is forming.
Yes doctor, there will be a war.
Yes doctor, there will be blood.....