A chinese Mid Master Yi and Korean mid Yi inspired me to make this guide and many of the tips come from their games.

Chinese Yi: https://space.bilibili.com/256872101?from=search&seid=13741589767636378288&spm_id_from=333.337.0.0

Korean Yi video: https://www.youtube.com/HappyChimeNoises （His video on a korean mid Master Yi)

I have no affliations with any of these people.

Master Yi mid gives you better snowballing potential and comes online faster than jungle if you are able to snowball. Plus it is arguably more interactive and enjoyable than jungling and requires you to master Yi's (haha) mechanics.

PROS

- Off-meta
- shuts up people calling Yi brainless
- good snowball potential
- good against assassins
- decent sustain with W
- Good diver
- Good scaling

CONS

- Heavily relies on q to do anything in lane
- susceptible to ganks
- no utility
- useless if behind
- not as mobile as people think
- weak before items

Yi is a good pick against assassins because he can nullify their burst using q and w. He is bad against champions that severely outranges him, champions that have alot of cc (Galio), strong early game champions (Sett, Renekton) and tanks that are able to survive his early game burst (beatable after 1st first item that is not duskblade).

You deal enough damage with only 3 items . What you need is to survive in order to fully dish out your damage. Thats why steraks and Randuins are good becasue they give you the highest tankiness out of all the other items. if you are dead, you can't do damage. Ravenous Hydra is the best if you need healing because it has omnivamp which on-hit build benefits, however it's stats dont really suit Yi and its passive is only useful if you are split pushing so not alot of people build it.

Domination

Hail of Blades

This rune is essential to Mid Yi and gives you the strongest early game burst and allows you to actually be relevant against other champions. The reason why I don't run Lethal Tempo is because although you gain alot of attack speed it requires time to set up and you will be losing hard before you get it stacked. You don't really have a way to chase early game as you will be using your q to engage and your q has a very long cooldown early game that doesn't refresh fast enough for you to win trades unless its a SUPER long trade. Yes Lethal Tempo scales better but Hail of Blades enable a much more active and aggressive playstyle that makes your early game actually not troll. PtA is better late game but is not as good early game as HoB, fleet footwork is unneeded as you have W for sustain in lane.

Sudden Impact

Gives you lethality for more damage

Taste for Blood

Good for sustain in lane when you need it

Ravenous Hunter

Although this rune has been nerfed so many times, it is still the best option so far. Master Yi doesnt really use items enough for Ingenious Hunter to work, he needs in-fight sustain and omnivamp fulfils that role. It also synergises with on-hit and fulfils the lack of lifesteal in the duskblade build. Other hunter runes are viable but not as good: ms is good for roaming but it only works out of battle and your ultimate refreshes on kill anyways so late game it will almost be up all the time.

Precision

Conqueror

Got nerfed, LT is better as it gives you attack speed

Triumph

Master Yi synergises super well with this rune because he gets multi-kills alot so it gives you alot of clutch healing. PoM is not needed as Yi doesn't have mana problems and you dont heal alot so overheal is pretty useless as well

Legend: Alacrity

Best rune out of the other two in terms of damage and utility. More attack speed = faster q cooldown. Bloodline is viable if you are running crit without duskblade and Tenacity is pretty bad due to the reasons stated in the merc boots section.

Coup De Grace/Last Stand/Cut down

Viable but very hard to replace the other sets of precision runes but if you want to run them: CDG > Cut Down > Last Stand

Resolve

Demolish

You can run it if you are planning to splitpush but for reasons that I will say in the mid-game section it is not recommended

Second Wind

The reason why we even pick this secondary tree. Helps you to survive poke

Bone Plating

Good against burst but you already have your q to counter assassins. Only consider running against bruisers that you know you are going to struggle against.

Conditioning

You are not a tank. There are better options for scaling runes so don't even consider this unless you are playing Tankyi especially when you can't pick second wind or bone plating when you get this.

Overgrowth

Its alright but is the best rune out of the two other. It gives you max hp but there are so much hp% damage in this game that it only helps you a little bit in survivability.

Unflinching

Tenacity bad

Revitalise

You don't have shields and you do not heal alot

Sorcery

Nimbus cloak

Master Yi actually does benefit from more ms as it allows him to stick in top of his targets better. Decent option for mobility

Transcendence

Untested if it fully refreshes Q after a kill. On hold for now

Celerity

Movespeed good, only take this if you are running nimbus cloak too

Absolute focus

Haha you are a melee assassin there is no way that you are gonna be at high hp for more than 0.5 seconds

Inspiration

Glacial Augment

I have seen someone on reddit saying that they ran this on top lane and it works but I have not tested it myself. I fail to see how this is good though.

First Strike

Needs more testing. Theoretically good as it boosts economy which Yi needs but seems better on jungle because you are playing a melee midlaner Yi and it is difficult to always be the first to strike.

Unsealed Spellbook

He is not very dependant on summoner spells and he needs offensive runes to function as a proper champion early game

Hextech Flashtraption

Master Yi is not dependant on flash.

Magical Footwear

viable but there are better runes in other trees

Perfect Timing

S T O P W A T C H
Praise our lord and saviour
Only works once though

Future's Market

Anything that boosts economy is good for Yi as he is very item dependant. This allows him to get his items earlier for an early powerspike that alows him to snowball.

Minion Dematerialiser

This is usually run by pros on other champions on specific playstyles and I am not good enough to comprehend the possibilties to this rune. Would be glad to see a guide or comment that explores the possibility.

Biscuit Delivery

You do not have mana issues and you have your W for sustain when you are low. Not needed

You can A-W-A to get an auto attack reset. You can either do this by tapping w twice or press W then immediately click on the enemy you want to attack. This tip will give you an unsuspecting burst damage that will option surprise enemies and give you a kill. However, the cooldown of W is very long and you can also use it to survive burst and for sustain so only use it when you are in an all-in.

Q flash instead of flash Q. This is a mechanic called buffering in which you queue up an ability to be used instantly after certain commands. The reason why we want to do this is because normally if you flash q there will have a delay where you need to press q after you flash. This delay is caused by you being human and not having machine reflexes. If you flash Q however, your q will activate instantly after you flash giving the enemy no chance to react to you.

Try to stack at least one stack of your passive before you engage which ensures that the last hit of your HoB is a double hit making maximum use of your rune to ensure burst.

Try to activate W at the last moment before you get hit by a tower shot to mitigate its damage. This is currently a bug that basically means that Master Yi's W damage reduction is way higher than it should be at the immediate moment of its activation.

Level 1-2 Cheese

DON' DO THIS AGAINST STRONG LEVEL 1 LANERS (bruisers like sett)

At level 1, when you and your oppenent player reach lane, try to directly q on the enemy laner and trade with them. If the enemy laner has a brain or tries to fight you (most likely they will lose) they will move back to their tower. This is why you need to master attack-move so you can get as much autos in as you can.

After you back off when the enemy laner is near their tower try to reverse kite them when they try to retaliate, meaning that you try and auto attack them when they try to auto attack you. Most ranged laners will try to auto you when you backoff so use the window of their auto attack animation to move close to them. You will be able to get a few more autos off if you are lucky. AT THE SAME TIME try to auto attack minions in between windows where you can't do anything in order to get your q up again. You will inevitability get damaged by minions which means that you may not win the trade (but atleast you will go even) but it doesn't matter that much if you do the steps perfectly. At this point if the enemy laner is close enough (out of tower if they followed you) and you followed the steps your q should be up again.

All in them to get 1st blood. If they stay back then go to plan B: the level 2 dive.

You should have minion advantage now since the enemy minions will be too focused attacking YOU instead of your own minions. Try to get level 2 before your opponent, get E (try to zone them) and push the wave into their tower. If they foolishly stay under tower you all in them and they die. This works better in lower elo because people consider Master Yi to be a scaling 'Weak Early Game' champion and underestimates his burst damage. At higher elos people will respect your damage and will not give you a chance to get on top of them for you to cheese them. In this case if you are against squishy champions that has no escape like Kassasin and Xerath you can try to poke them with your q by targetting minions near them, get level 2 1st and dive them.

Laning

If you managed to get an early game lead you can dive them with relative ease since Yi is a good diver. If you did not manage to get an early game lead (failing the cheese or get early ganked) play it safe because you are weak between level 3-5. You rely heavily on your Q to outplay the opponent so DON'T USE IT when you need it to dodge the opponent's important abilities (sett's E and Pantheon's W). You can use q to poke the enemy laner and try to keep your q up asap by auto attacking minions. You can use W to heal when you are low or use it as an auto attack reset (auto attack once, W then cancel it immediately following up with another auto attack) which may sound pretty trival but ALOT of times using it and not using it decides on whether you get a kill or die so try use it in crucial situations like during dives and all ins.

After you get your ultimate, you can try to all in the enemy laner if you are even or ahead. Alternatively shove the wave and try to roam because you thrive on kills and the sooner you come online the better.

Contrary to popular belief, Master Yi is actually the strongest mid game than late game. Most builds only requires 3 items to do high damage (if you are running duskblade you spike on second item or eclipse it spikes even harder at 1st item) and at this time no one can really one-shot you so you can get multikills easier.

DO NOT BE THE FIRST ONE TO ENGAGE

This may be obvious for people who have played Yi for a while but for new players DO NOT think that Yi is this invincible behemoth when you become fed. He is at his core an assassin and at best a bruiser so you die easily. Crowd control renders you prone and you will blow up even if you are fed. Wait for your teammates to engage or the enemy team so that you don't get targetted by cc and die. Try to flank or get picks because you are strong enough to duel and once you get a kill you are able to snowball and get another.

If you are playing duskblade, you will be trying to join teamfights for the majority of the game. Your job is to burst down the enemy carry and get a reset which you can evolve to multi-kills. You will rely mainly on your q to do damage and it does the most damage on single targets so play like Khazix and target isolated champions. Once you get a kill its not recommended to auto attack immediately as it will break your invisibility so try to reposition and get the next high priority target instead.

Split pushing is still viable but he is no longer the ideal split pusher like the good'ol days and you are needed in teamfights so don't do it unless you HAVE to.

If you are running crit especially duskblade you will not be able to 1v1 alot of champions (bruisers and duelists such as Sett and Yone) so your job is to focus on the carries. At this point split pushing becomes more dangerous as there are alot of champions that can outduel you so play for your team and objectives. Vision is very important as it allows you to set up picks or prevent one from the enemy team. You also need to be extra careful as one mistake lategame can mean death to the entire team especially if you are the carry.

To excel on Mid Yi you need very solid basic mechanics. These basic machanics like kiting and attack-move can be used on every champion but you need to be good at them since there is only so much you can do with Master Yi in lane. Master Yi lacks the mobility, sustain and lockdown potential in order to go toe-to-toe against many champions so you can only win by out-witting them. As an assassin mid-laner you need to roam to fully function so having a strong macro is a must on Master Yi.

Don't being toxic and take breaks when you get a lose streak. If your team is struggling you typing 'jg diff' in chat isn't gonna help anything and it will just tilt your teammates. Encourage your team when they make successful plays and they will be more willing to save your ***. If you are on a lose streak take a break from league because even if you don't feel like it, your mind is affected by thoses losses and will influence you to make irrational decisions.