Hello Everyone, my name is Rick, IGN: Get Ricked and i play on EUW. I've been playing since season 3 and started as a top lane main, transitioning into jungle a few seasons ago. My peak was Diamond 2 and I have been diamond for 5 seasons and trying to get back.

I've played Kha'Zix for all the time I've been playing jungle and I love the champion. I will go into the best build for him and the different ways of playing him and what makes him such a solo queue beast.

Pro's:

Strong duelist
High damage
Huge snowballer
Strong vs squshys
Mobile
A ton of stealth
Good scaling

Con's

Weak early clear
Weak pre 6
Squshy
Bad from behind
Bad into tanks

Pre 6:
Before Level 6 you mostly want to farm up and look for clear opportunities. If you hesitate whether a play will work just go back to farming. This is your weakest point in the game so you don't want to take unnecessary risks. You lose 1v1 versus most champions at this point. Ward out your jungle entrances so you don't get invaded early. Your biggest goal right now is to cs and not fall behind.

Early game pre 6

Now you have a lot more options. You can 1v1 most enemy junglers now and you should look to fight them if you have the chance. Otherwise try to make ganks happen or farm up. When the enemy jungler is on the other side try to solo either the drake or the herald. Kha'Zix solo's it extremely well with the isolated Q dmg.

Mid game/late game(duskblade completed)

In this fase you will get into teamfights. Kha'Zix is actually a really good teamfighter with duskblade. You want to go in and target one of the carry's then pop AA>Q>W and then go into stealth with your R or if the target is dead with your duskblade. Keep popping out of stealth and use the same combo. The extra dmg on your passive AA will keep refreshing when you get out of stealth. Also you make it very hard to target you when you keep going in stealth. Also use the stealth to resposition. When you can jump in to make a kill do it and use the stealth from the duskblade or your evolved E at lvl 16 to get out.
Aside from teamfights you want to look for picks. Get vision and try to catch squshy champions in their rotations. You can blow up most isolated targets so use that to your advantage.