Hey this is my first guide so be nice, Ive been playing master yi for a little bit now im not lvl 30 im lvl 24 and this have been working pretty well for me and i would like to share this with you all master yi gets bad rep for being an easy champion to play. With this build i find that i have enough sustain to be able to stay in lain longer get more kills and minion farm along with not having to be fed to have a ton of AD to do alot of damage and be a great team player, this build has mainly been tested in 3s games i haven't tried this build in 5s. i have taken a little bit from some other guilds id like to give them their deserved credit the mastery's belong to DEWO in his Master Yi, Cutting with Wuju Style. __(NOT A SPAM BUILD)__ feel free to check his build out if you please http://www.mobafire.com/league-of-legends/build/master-yi-cutting-with-wuju-style-not-a-spam-build-272

With all the Arp you get from the marks and your quints you will be cutting through the enemy champions in no time early and late game and since master yi is so squishy early game and late game the Armor seals will help make you more durable feel free to buy the Tier 2 Runes they arent as strong as Tier 3 but they will help and the Cooldown reduction will help you spam abilites more letting your auto attacks deal alot of dmg but still letting you get extra dmg with other attacks and let you hit alot harder with wuju style more often also a lower CD on Alpha strike will allow you to catch running champions and give you an escape mechanism Alpha strikeing to minions [ even allowing faster farming ]

start off with boots and 3 health pots the health pots will help you stay in lane early game and keep your farm up or survive harassing enemy champs you to should harass with your Q buy Berserkers grieves when you can for the extra attack speed i tend to like to go back and get Tier 2 boots and a dagger at the same time for alot of AS now you need to save up for 2 vampiric scepters the life steal will be a big boost in sustain and damage for your lane soloing top or laneing bot it will help when you can turn one vampiric scepter into a executioner's calling then head back to lane when you can then go back and grab a BF sword the AD from it will be a great help then quickly try to change the BF sword and vampiric scepter into a bloodthirster and right now you still have your dagger form a zeal with it when possable then grab a second dagger when you can and change all of it into a phantom dancer now you have alot of AS and AD and LS you should be chunking health and when your blood thirster is maxed out you will be close to unkillable now you need to build a little resistence depending on what the enemy champs are heavy with depends on what you build first if they have alot of AP build your force of nature first if they have alot of AD build Thornmail first you should have full build by now but in 3s you probably wont get that far before the game is over unless you are fed.

Like i said guys this is my first time making a guide so be nice and please offer me some pointers on what i can do to improve because i know i have alot to learn about LoL and i intend to do my best and make stronger builds for more champs please feel free to take my build and form it to your likeing maybe you dont like the thornmail force of nature and like warmogs atmas better give me advice on what you would do to change my build to make it work share your exp. with the build tell me how you liked it please leave a comment letting me know what you think
but anyway thanks for reading hope this works for you