Note: So far I've spent around an hour on this guide to include the main points. I will update this is the future to add more detail and decorate everything so everything looks prettier.

Master Yi is an easy to play but difficult to master champion. I have been maining him for the past year now and after trying many different builds and play styles through trial and error, I've found what works and what doesn't.

Why you should jungle:

After playing numerous games as master yi, I began to notice an important pattern. I was winning about 80% of my games as jungle yi but only 40% as lane yi even though I very rarely have a k/d ratio lower than 1.

It was then that I realized the importance of creep distribution. As yi, the more creeps I took in lane, the higher the chance my team had of losing unless I carry them very well. Farming yi's core items is vital but it is very easy to do even as jungle, as long as you gank decently early on.

If you must lane with yi then take top lane since early game, yi in bot lane is very weak and will get ganked, pushed to the extreme.

Pros:
+ easy to play
+ good at farming
+ good at destroying towers
+ good for cleaning up battles/chasing
+ best melee burst damage in game (with my build)

Cons:
- very squishy
- weak early game
- weak to cc
- weak in team fights
- hard to master

Once you have the core items, you can do pretty much whatever you like depending on the circumstance.

The core items are:
1. Berserker's grieves
2. Wriggles's lantern
3. Phantom Dancer
4. Infinity Edge

Highly recommended 5th item:
Last Whisper: I've experimented with and without it and it does make a decent amount of difference in damage output in most cases.

You can get trinity force if the game will last that long and you have enough gold, frozen mallet for the hp and slow, another phantom dancer for insane crits and movespeed so you don't even need the frozen mallet slow, MR items, even hp items, whatever floats your boat.

Jungle:



If you're jungling, this is pretty much essential.



This is pretty useful for the early ganks once you've gotten your first red at level 4 and pretty much any other time in the game for chasing, escaping, ect. It is to a degree interchangeable with flash

Lane:

This is very useful if you're going to lane and helps a lot late game too as it can help you chase an enemy near a ward far away, save you and allow you to teleport to the other side of the map when enemies try to ambush you, get you to the enemy base quickly to backdoor, ect.


Again, this is interchangeable with flash but I prefer using this.

This is the order you want to normally use for most circumstances.

1. small golems
2. wraiths
3. wolves
4. blue
5. small golems
6. red
7. if you see a lane that is pushed and enemy is around half health, head over to gank. Otherwise, continue jungling or go back to base to buy more items before attempting to gank.

For those who don't know this is master yi's lore

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' 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.'' -- Soraka, the Starchild