Hey guys this is my first build here i play on NA this is kind of a test build. It works and everything but you will notice how i have no skill at all in writing a guide/build lol

Pros
Great burst one you get your BT
Awesome farmer through out the game
Great harasser.
When played well can carry a team.
Hes got a great ultimate which can COME BACK after you get a kill and can be used to chase or escape.
Great pusher.

Cons.
Squishy with this build (life steal helps).
Will get focused at team fights.
Not well suited for 1v1 unless he got ultimate.
Get very cocky from the insane damage and life steal.

I choose this set of Masteries because they just work well on him..A nice amount of armor pen.
Some damage/life steal and crit with his build A little MR and armor just for a Lil more survivability. I really don't see what else you can choose on him!

Well one of the most important part of this is his build..Some of you guys are wondering why start of with a dorans ring? well..I'll tell you about this later.

i get boots and rush zeal because zeal + boots of speed is pretty much same speed as berserkers greaves but with bonus attack speed / crit will go well with his ultimate. Next i build the zeal to Phantom Dancer this is a great item with a load of crit with bonus movement and attack speed..made for yi..
next i get the berserker greaves just for some extra speed.
i get vampiric scepter for some life steal with the PD
i get a IF for more damage and crit. once you get this item your a REAL beast >:O
i get to Blood thirsters next they give a load of AD and life steal (just farm yi is a great pusher)
i end if with another PD giving him an Whopping amount of crit.

(EARLY GAME)
Well most of you guys are wondering !!WHY Q FIRST AND NOT E WHY NO RANKS IN W EARLY!!.
Well since yi is not so great at early game i play him as a harasser now I'm gonna tell you why i get dorans ring first on yi Alpha strike has quite a high chance of hitting 400s on (gets higher as your put ranks in it)minions. So using it when ever it off Cool Down will get you loads of CS (creep score) and do great harass the dorans ring helps by giving him 100health 15 ap And a nice mana regen making you never run out of mana while spamming his Q

(MID GAME/LATE GAME)
Now i never use my Meditate i really find no use for it sure after getting a kill you can use it to regain your health but, with the amount of life steal you got just go smack around some creeps nd that's that.

your no gonna be using your Q much anymore you should only using it to Engage a enemy if there escaping what your gonna focus more on is your Ult and wuju style when ever you see some one vulnerable (over extending, no allies around) its pretty much a free kill.
Your job at team fights is to drop there AoE bursts AD carrys AND to go in after your tank and a Off tank if you go in to early you might as well go try and play as a minion.

I'm sorry i have no picture of stats and items this is just a basic way of playing yi.ITS SO EASY all you gotta do is farm a bit early game and once you get your B-T start melting away there squishy s! Anyways i hope this helped you out and just remember thorn mail is you #1 enemy.
Hehe this ain't really a summary know is it. :P hopefully i can finish this build soon there's meany yi builds and such and this probably aint the best.