How the fuck do you kill a Zeratul? He shreds backlines so fast, and has so many god damn escapes.
Edit; Playing as Leoric/Johanna/Anub
Try playing as Zeratul. Try and figure out what the hero needs to do to be successful. Then you can start thinking about where you would be if you were a Zeratul while playing another hero, who are his targets, how would he try to get to them and how do you get to him to stop that.
Anub can get AoE damage on shield activation or Radiance, I forget what the talent is called, the fiery aura. Both are great for revealing invisible heroes. The aura talent requires longer proximity while the shield talent requires the use of an active ability.
Johanna's shield flash is great for revealing invis units, as is her vortex skill but she typically needs a damage dealer with her to finish off a Zeratul who will eventually blink away. Nova is easier for Johanna to keep a hold of.
Loeric's kind in the same boat as Johanna, your swing can slow and reveal but you can't really do much about either getting away, although Drain hope can give you some decent harass.