User blog comment:StrategicMagic/Shaco Solo Top - Another Way/@comment-4794115-20130123235133/@comment-5194571-20130124114648

Shaco is a counterpick to Kha'Zix for the following reasons:

Early on, Kha'Zix IS squishy, that cannot be denied. Shivs and boxes will hurt him. If he falls for the lvl 1 trick and takes at least 2/3 of his health, he will be zoned with ease. This is even more true if you kill him.

Kha needs to be in explosion range to heal. That means he needs to be right next to your minions. A Shiv to the face (remember, you are maxing this first) will do enough damage to cancel out his heal.

If Kha takes 1 box + Shiv, then goes to heal, but you throw another Shiv, you still out damaged his heal. That sustain can't last forever.

Kha does have a lot of burst, I admit. Are you farmiliar with the Shaco trick where you avoid things like Karth ult and tower shots by popping R at the right time? The general combo of Kha'Zix is to leap onto you, using W and Q in midair. Time your R right and he blew all of his cooldowns for no damage at all. Follow up with Q and your clone, plus a Shiv or two and you won.

Executioner's Calling will reduce healing of the target enemy champion. Getting this will mean sustain won't do much. It's also a fairly cheap item.