Hey people, I'm kinda new to mobafire and all but I have been getting quadra kills with yi in all my recent games so if you want to be OP to the max, ITS ALL HERE!!

I used attack speed, attack damage and magic resist runes all for an equal balance between defense and offense. The mana regen is for Yi's sucky ammounts of mana. I used Crit Chance because yi's crit does a hell of a lot of dammage. (you can see this early game right after you alpha-strike someones butt)

For the masteries, i have been using Pantheon's masteries from an old build and it seems to work so i continue with that. I use these masteries for Twisted fate, Nunu and jax and it works!

Please forgive me if the descriptions in this build are not as intricate as others, there's nothing much to say other than whats shown.

Exhaust is a great spell for pro yi's and its good if you're chasing after someone, and they flash away. You use exhaust and they have no chance against you.
"ew, heal is for *******" "That YI SUCKS! HE HAS HEAL!"THAT IS ALL ********! (EXCUSE ME) but c'mon, you gotta do what you gotta do, so if you are a new-Yi then use Heal and stay alive in lane. Ignite helps on the early/some of late game killing.

Now I can talk!
You want to get boots first to run after your enemy and kill him before he chickens out to his turret. MAKE SURE YOU HAVE AN ALLY HELPING YOU OTHERWISE YOU WILL WILT AWAY LIKE A FLY.
You might wanna team up with someone with a slow so that you can pwn and maybe ks. but that's up to you.
LIFE STEAL IS KEY! this is the main thing, you need SURVIVABILITY to keep you laning effectively. you dont wanna miss out on lvling and lifesteal can help you with that. For a lifesteal-attack speed combo, a Starks Fervor is optional.
Phantom Dancers are also a MAJOR boost to your crit chance and Attack speed while Black Cleaver helps you on the damage/armor pen. side. The blood thirster helps a lot on the lifesteal part. So, during late game, when you're taking on 4 people by yourself, people might be like "why the hell isn't that yi dying" and to that you say, "Life steal BIATCH!"
I will recommend for late game, for just a bit of extra health and AD, take a Frozen Mallet.

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YOU DONT WANNA FOCUS MEDITATE UNLESS YOU ARE DOING HORRIBLY!!!
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build up your Wuju Style for pwnage damage and then build up alpha strike!, meditate comes last since your lifesteal takes care of most of the healing. If you need to heal early game without going back to base, you might wanna go in the jungle and steal the life off of those creeps.