Master Yi is a champion of many possibilities. He can be played either AD or AP. When played AD, he can be glass canon, tanky damage dealer or offtank. I think its best to build him as tanky damage dealer. You still have absolutely amazing damage, while having decent health with good MR and Armor.

Keeper of the ancient art of Wuju, Master Yi is a mystical warrior from the isle of Ionia. He descended from one of the few tribes dedicated to the preservation of Wuju, a martial art founded with the principles of absolute spiritual awareness of one's self and one's enemy. When the armies of Noxus invaded Ionia, Master Yi joined in the Ionian defense to fight the craven enemy, bringing his village honor through his unparalleled mastery of the blade. The ensuing battles ravaged the land, but no conflict inflicted as much horror as the day the armies of Noxus closed in on Yi's village. Left undefended, the village became the unfortunate test subject of the latest invention by an up-and-coming chemist, now known as Singed. The remains of the village that Master Yi returned to were so horrific that it remains a festering scar on Ionian history. To this day, no Ionian will ever publicly speak of what occurred.

After the Noxian invasion was contained, Master Yi fell into a deep isolation. For years, he trained morning to night, speaking to no one and refusing offers of consolation by fellow Ionians. The only thing stopping him from madly charging into Noxus battle lines headfirst was his pledge to keep the Wuju style alive. Even though he seethed with impatience, his rage became a tool for sharpening his practice of Wuju, developing stronger and deadlier skills for his eventual vengeance. The only thing that roused him was news of the League's formation, and Noxus's subsequent enrollment in the League. Master Yi now brings his mastery of the blade to the League of Legends with unflinching purpose: to avenge his kinfolk and end the predations of the Noxus once and for all.

"The art of Wuju lives on in Master Yi, and is plunged through the hearts of his foes."

Many Master Yi start with Cloth Armor and 5 Health Potions instead of Vampiric Scepter, which is better since new jungle. Here are reasons why:


You don't waste your money on potions. Because of that you have 175 gold more. That is a decent amount in early game and you'll get your Wriggle's Lantern way faster by buying Vampiric Scepter.

You don't need to time your potions. You don't have potions and don't have to rely on them to jungle. You just auto-attack and you have health income, especially with Wuju Style active.

Higher health at end of clearing. On this route with Vampiric Scepter you end with 3/4 health, ready to gank. If you choose Armor+Potions combo, you have to go back after completing, which means later ganks and buff waiste.

While some might think that jungling is basicly about killing neutral monsters and gaining exp and gold, it's much more than that. That is only the basic thing, but there are a lot of other things you must do:

Cover your ally's lane
If there's a need, so he can go back, restore health & mana and buy few items. You have to be careful when doing that, because you can unintentonaly push his lane and screw his early game farming.

Time your ganks
You need to time your ganks. There is no point in ganking, when your bot/top/mid lane has pushed enemies to their tower. Ganks when enemies are overextending. That is the time they are most vulnerable and with good laning buddies they might be even tricked into towerdiving right before you gank.

Ward your jungle
In early game, your support won't be warding your jungle, so it's up to you. Ward in strategic points in your jungle which cover most of your camps. Counter-jungling is nothing rare in higher level games and you mind find yourself without red buff because of that. If you ward, you can see your enemy counter-junling. Gank him, and instead of gone buff you have extra kill. After getting Wriggle's Lantern that shouldn't even be a problem.

Tell your team to protect you and your jungle at start
Many strategies involve something like stealing wraiths at start so you can screw enemy jungler. Well there is a simple solution for that. For example in you're staring at gollems, tell your top to protect you from bush, mid to watch over wraiths, while bot covers your blue. After enemy lanes have shown up, they don't have to protect anymore.

Share buffs
You need to share your buffs. Your mid carry that has huge mana requirement and needs lower cooldowns will benefit much more from it than you. Sharing buffs can contribute to your team wining the game. Red buff needs to be shared in some occasions too. If you have Frozen Mallet and you're AD carry doesn't have slow, leave it for him, he'll benefit more.

Dragon and Baron
These two are most important neutral monsters in game. You have to fight to gain control of them. If somebody has to die for it, it may be worth it. For example let's say you're doing dragon. Your ally goes and defends you. He is killed. You should take that in advantage and finish dragon quick. With that kill they got 300g, while you got 5x190G with dragon, which equals 950G. That is tree kills worth. Baron is important because of buff, which can decide who wins.