Well I discoverd this build myself and I am only 14 years of age. I did the runes to trigger 1 of the passives at level 1 or 2 then you get dorans blade to trigger the other passive and the masteries so akali wont be squishy early game

I did the runes just like this because the Quintessences give 14 ap and all the others give 3,4, or 5 per level. so at level 2 forsure you will have the second passive read masteries to see why

I did the masteries just how they are because it gives 6 armor 2 magic resist 2% dodge (which can save you in clutch moments) and blocks 4 damage from minions and 2 from champions (just auto attacks) for when you are laning and attacking someone next to the minions, (which can also save you in cluth moments) 48 health which is handy for not being to squishy,and 4% attack speed and ability power (which is handy for activitating you passive for the ability power and the reason you went down the defensive line) and 4% percent reduced damage.

then you want to get improved exhaust so you can lower armor and magic resist, ability power per level, 4% cooldown reduction, and 15% magic ability pen.

you want to get the boots of swftness to help you run away when you don't have enough health or minions to dash too, 2 hextech gunblades for survivability and sustainability, a rylais chrystal scepter to slow fleeing enemys and and health for more survivability, a death cap to increase your ap a lot!. and a lich bane for the passive which is great because you will have between 900 and 1000 ap

I have it setup I think the best way (imo) for the most damage

exhaust for those clutch moments and the mastery helps it out tremendously to get a first blood early game, and flash to flash into range to use your dash or to get out of range of champ or a skillshot that could kill you

you want to focus much on early game farming because you need it to do a snowball effect when you get your items to get your kills to carry your team and kill the ad carry in teamfights :)

you always want to come in team fights 2nd or 3rd but don't get focused because you want to kill the carry you don't want to be doing the tanking you want to be killing the ranged squishys in the back or the ad carry

Pros: you nuke hard, heal your self, and you go stealth
Cons: you can get countered by an oracles or ward, and you get squishy late game

So this was my first guide I hope you all liked it :) please like it