Kha'Zix is an realy strong chamion. he is hard to counter and hard to gank cause of his E.

Look at my tips below

Farm is realy nice with kha zix. try to get more farm than 150 in 20minutes

Kha'Zix has the ability of evolution, and every time he puts a point towards his VOID ASSAULT ultimate, he gets an Evolution Point.
These points are used to permanently upgrade any of his abilities to an improved form with improved abilities.

-Evolutions-
TASTE THEIR FEAR - EVOLVED ENLARGED CLAWS increases the range of TASTE THEIR FEAR and autto-attacks by 50. Also, he now does 8% of the target's missing health in bonus damage (max 200 on monsters). Deals 45% more damage to 11.6% of the target's health against isolated targets.
VOID SPIKE - EVOLVED SPIKE RACKS changes from 1 missile firing strait forward, to 3 missiles firing in a cone.
LEAP - EVOLVED WINGS increase LEAP's range by 300, and kills and assists will now refresh LEAP's cool-down.
VOID ASSAULT - EVOLVED ACTIVE CAMOUFLAGE allows VOID ASSAULT to be cast 3 times, and Kha'Zix takes 50% less damage while invisible.

THE HUNT IS ON!
According to the lore, Rengar and Kha'Zix are enemies, and want each other dead. After a vicious battle between the two, Kha'Zix found Rengar to be a formidable opponent who he could learn some from. Kha'Zix wants to consume Rengar, learn his abilities and become the ultimate predator.
In game, once Kha'Zix has use all 3 evolution points, and Rengar has a Bonetooth Necklace with at least 10 stacks, and all players are alive, a quest starts called THE HUNT IS ON! and whichever of the two kills (or assists in killing) the other receives a bonus. If Kha'Zix wins, he gets a fourth EVOLUTION POINT.
If Rengar wins, he gets the item HEAD OF KHA'ZIX.

Try to get all creeps with your Q last hit