Welcome to my build on master yi, this is my first guide on league of legends.
Ok, lets go into a quick character description,
Hes one of the best dps characters in the game, and is one of the best farmers and pushers. Master yi can deal huge amounts of damage in a short time, but is extremely vulnerable to blinds/exhausts/stuns etc, and is easily harrased early game.

Pros
Great pusher
Great dps dealing large amount of damage
One of the best chasers and escapers with highlander
Can farm extremely well
He is easy to play

Cons
Extremely vulnerable to blind/exhaust/stuns etc
Squishy, always targeted first
No reliable escape without ult

This passive strikes twice every 7th attack. This is one of the reasons why master yi is such a good pusher and dps, if timed correctly can push hard, and harass effectively. Its especially useful in late game, when combined with the items can do over 1k in damage, killing the opponent before they have a chance to heal/lifesteal.


Yi Jumps through the field, hitting up to 4 enemies, dealing 100/150/200/250/300 +1 per ability power damage. This is especially useful for ap yi, but since this build is dps I won't go into that. This is Yis second most important ability, after highlander, as it can close distance easily, harass enemies early, and if used correctly to escape from a losing battle. However note that you CAN get killed while alpha striking.


Master yi channels, and heals 140/280/420/560/700 health over 5 seconds (+1.65 per ability power. This is mainly useful for ap yi, for dps yi it is dosent have much use. In early game the heal amount is too little to be of use, and in mid/late game lifestealing is much faster.


Master yi passively increases his attack damage by 15/20/25/30/35, when activated doubles the effect for 10 secs, but the passive will be removed until the ability is available again.
This is one of yis best abilities, as it greatly increases damage output, is great for farming, and pushing turrets, combined with double strike yi can push turrets quickly, it should be maxed early along with alpha strike.


Master yis movement speed and attack speed are increased by 40% and 40%/60%/80% respectively, and becomes immune to all slowing effects, for 6/9/12 seconds. Killing a champion while highlander is activated refreshes all abilities including highlander.
This is THE Best ability for master yi, what makes him such a owning dps champ, can be used for chasing, escaping, tower diving, pushing, and backdooring. One of the best part of this ability is the cooldown refresh, so once you killed a champion you can activate it again and get more kills! Also the immune to slow is extremely vital to escaping, and can escape from many situations.


Combo

Usually, when charging into a fight, use alpha strike in, wuju style, then highlander.

As you can see here I use and

I'll go through the summoner spells here


This is extremely useful for yi, slows a fleeing opponent down so you can get into melee range, also good for exhausting opponent then escaping. This comes in handy in so many situations, like ganking, teamfights, and 1v1s.


I normally use this for escaping, or chasing. Some people may argue that flash is better even after it was nerfed, but I usually stick with this. In my opinion ghost is much more reliable when escaping and chasing, and you often see players who flash get chased down, and players who ghost escape successfully


As I mentioned above you can use this but I would recommend ghost


You don't need this. Lifestealing heals more and dosent have a ridiculoud cooldown


Quite useful for moving around, especially for backdooring.

The ideal build

Start off with a and .

When you get to around 1000+ gold recall and buy .
For your next trip back buy a and a . If you have the money buy a directly.

By this point you should be ganking and getting a lot of kills. If not, stay back and farm until you have enough money for a Emblem of valour.
Finish the early/mid build with a
At this point it gets quite situational. If you are totally wiping them out, get a and build it into a
If the enemy is too strong, get a for some armor damage and farming

Good mid game
Not so good mid game