This is a guide to players who are new to Kha'Zix, and do not completely understand him yet. Before you rate the build please look over it.

The Mark of Strength was chosen because when Kha'zix first comes into the game his attack damage is slightly lower so i choose Runes of Strength to bump him up a little bit to be at par or higher than the opponents stats to ensure the kill early game.

The Seal of Resilience was chosen because Kha'zix being an assassin is squishy and takes heavy damage so he needs the extra armor for Survivability, Because a good early goes into a good late game.

The Glyph of Shielding was chosen because it goes into with what i said about the Seal of Resilience, and how Kha'zix is a squishy champion, it just helps against the ability power champion who are laning against you.

The maseteries were chosen to ensure that the early game kill will be easy to get. i put the points into the damage spots for that harder hit which is what you always want with an attack damage champion. However i also put points into the cooldown reduce and the magic pen slots. i did this because Kha'zix passive hits with magic damage not physical so if i spec into the magic pen i hit harder with my unseen threat. I then put points into the armor and magic resist slots because Kha'zix is a squishier champion so he needs that extra defense.

These items were chosen on a variety of different factors: armor, magic resist, AD, AP, life steal and other things that involve a good assassin.
I get the brutalizer first because it's easy to get early game and with early game and other champions have little armor the extra armor pen makes him hit all that much harder.
You then have a choice, mercury's treads or ninja tabai. If im laning with an Ahri im gonna get mercury's treads if im laning with a warwick im getting the ninja tabai simple as that, ninja tabai for against AD champions, mercury's treads for AP champions.
Then i get the bilgewater cutlass for two reasons: One, the active: the damage and a slow, that is great, especially if your chasing and your E is on cooldown just hit them with that and they are yours for the taking. The second reasons is the life steal, life steal is always good especially for an AD champion.
After that i get the hexdrinker and the maw of malmortius, This is for that extra survivability, both with the shield below 30% health and the magic resist.
I then get the youmuu's ghost blade because of the active and the stats, this can be good to finish that tough kill or to get away from a sticky situation used with your E it's not to hard to get away.
After that i get the hextech revolver and gunblade, this is because the spell goes with the passive (unseen threat) and the range of bilgewater's active is increased damage and longer range.
Then comes the mother of life steal the blood thirster why you would get this is self explanatory, LIFE STEAL! LIFE STEAL! LIFE STEAL!
I then finish the build with a trinity force, this is because it gives a little of everything pretty much. Need mana it has it, damage? trinity has it, running speed, heck has that too! it's just a good way to end a good build

There's a lot of thought that is put into the spell sequence. I chose this particular sequence because i feel that the E early game is easier for a lane gank being able to jump to the target and hit them with Q makes for an easier and more reliable combo than trying to hit them with your W which ends if you hit one target.

EVOLUTION!: The evolution pattern i see to be the best is if you just follow the line of abilities, first off the Q for longer auto attack range and harder Q hit. Than the W for a three prong barrage, this spell is amazing for clearing out large waves of minions, or even jungling. Then i upgrade either my E/R with this it is a little more tricky because you have to realize how your doing in the game, when you think your going to be in high risk situations and team fights where you need to jump in and out then evolving E would be the best option because the cooldown is reset on assist and or kill. If you're being more of a lane switch and an assassin then R would be the best considering you get 3 times to use the ult and damage is reduced by 40% while invisible, and then it also comes down to preference.

The summoner spells were to hard to pick out i chose them because there good for any ganking champion.

Ignite: I chose this because it helps to ensure that your going to get the kill at all times when the enemy champion is at low health
Flash: This was a no brainer this move is always good to get out of bad situations or chasing someone to get the kill. This can also be incorporated with ignite to get the kill.

Pros: High damage, easy early kill, very mobile, easy to use.

Cons: Squishy early game.

This build is made to inform you on how to build Kha'zix and how to use him.
I hope you liked it, i take all changes or comments into consideration so tell me what you like (:

P.s. Feel free to contact me in game to discuss the guide personally one on one, Maybe we can play a game or two also!(: bye!

-Nestius