Hey guys! This is WitsEnd, and this is a guide on how to be a good Master Yi. Yi is one of my favorite champions, because of his natural moility and ability to unleash damage. However, Master Yi lacks survivability and has zero crowd control. He also has a slightly weaker early game, but snowballs lategame. But, as I will explain in this guide, there are always ways around that. I will primarily be explaining the standard crit build, but there will be a section where I explain the Guinsoo's Build as well. Enjoy!

Pros

High mobility
Mad late-game scaling
Insane damage output
AoE and true damage
Simple to play
Good jungle clear
1v9 potential

Cons

Low survivability
Weaker early game
No duelist potential until mid-late game
Zero CC
Easy to counter

Master Yi has a very simple and straightforward kit, almost fully being oriented around attack speed. He has a good clear with his Alpha Strike, solid AD damage output with his Wuju Style, and decent sustain with Meditate.

Passive After landing three basic attacks, your next basic attack within 4 seconds will attack twice, dealing 50% of your AD as additional damage. This second attack can critically strike and applies on-hit effects. If the first attack kills a unit, then the second attack searches for a nearby enemy and attacks it, prioritizing killing blows. Double Strike helps reduce the cooldown of your Alpha Strike and helps with your jungle clear.
Advanced spell details: A Double Strike will reset all double strike stacks and add a new one. Every consecutive double strike within 4 seconds will therefore happen every 3rd attack. With a fully stacked Guinsoo's Rageblade it will happen every 2 attacks.

Alpha Strike Go untargetable and jump onto a nearby enemy, striking it and up to 3 nearby enemies for 25/60/95/130/165 (+100% of AD) damage and dealing additional 75/100/125/150/175 damage to minions and monsters. This spell can critically strike, and basic attacks reduce the cooldown of this spell by one second. With a range of 600, this spell has a higher range than Flash. Many new players make the mistake of Q-ing on to an enemy instantly during a gank, but this is a mistake. Because of Highlander you will be able to catch any enemy easily without Alpha Strike. Use your Q only AFTER the enemy uses an escape spell to secure a kill. This is the first skill you should max.
Advanced spell details: Alpha Strike grants vision of the targeted enemies. Alpha Strike prioritizes the closest enemies within 600 units after striking the first target. Master Yi will reappear at the initial location if the initial target dies or if he is too far away as the blink is completed. Enemies who become stealthed after the lock-on will still be followed, but enemies who are stealthed cannot be targeted or hit by Alpha Strike bounces. Auto-attack cooldown reduction applies on structures, but not when Master Yi is blinded. You can use summoner spells while in Alpha Strike. If targeting an enemy champion, you will auto attack it after finishing Alpha Strike. If it is a minion or a monster, you will not auto attack automatically. Alpha Strike counts as movement for the purposes of energized attacks/charges. Alpha Strike damage is calculated individually for each bounce. However, critical chance is calculated together, so hitting multiple enemies with Alpha Strike will increase your critical strike chance on each bounce. Alpha Strike resets turret aggro, meaning additional damage stacks are reseted upon entering untargetability. Damage is applied to targets after leaving untargetability, however, so it will attract turret aggro.

Meditate Channel for 4 seconds, healing for 30/50/70/90/110 (+25% of AP) health per second. This amount is increased by 1% per 1% health that you are missing. While channeling, gain 50/55/60/65/70% damage reduction. This damage reduction is halved against turrets. While channeling, pause the duration of Wuju Style and Highlander and gain one stack of Double Strike. A good source of sustain in the jungle, this is a great tool both in duels and in poorly-organized dives. When an enemy goes untargetable, it is always a good idea to Meditate both for regen and damage reduction: otherwise you will waste time. Also, in clutch situations where you are about to die to tower, you can Meditate to increase your chances of survival. Max this skill last.
Advanced spell details: Meditate does not reduce incoming true damage, and hard crowd control (stuns, silences, suppresses) interrupt its duration. Each heal per second is calculated individually, meaning as you heal more your healing will decrease because your %missing health will decrease.

Wuju Style Passively increases your AD by 10%. Activate this spell to increase the damage dealt by your auto attacks by 18/26/34/42/50 (+35% of AD) true damage for 5 seconds. The passive effect is lost while on cooldown. The passive AD is almost irrelevant because you will almost always be spamming Wuju Style whenever it's up. Extra damage is always nice: this skill is self-explanatory. Try to save this spell for especially difficult camps or when you're going into river, because a potential gank or a duel with the enemy jungler might follow. Max this spell second.
Advanced spell details: Wuju Style has no cast time and will not interrupt other casts. Bonus true damage does not affect structures and it does not apply bonus damage on critical strikes. Bonus true damage cannot be blocked, but if the auto attack doesn't land it will not be proced. Passive AD is kept while Wuju Style is active but is lost upon cooldown.

Highlander For 7 seconds, gain 25/35/45% MS and 30/55/80% AS and gain slow immunity. Kills and assists increase the duration of this spell by another 7 seconds. Passively, reduce the cooldown of your other spells by 70% on champion takedown. Popping this spell before a gank greatly enhances your damage, and allows you to catch enemies who are trying to run away without locking on with your Q. The CDR plays a huge role in group fights.
Advanced spell details: Highlander has no cast time and does not interrupt other casts. Slow immunity extends to all slows, including charmed and feared slows, meaning while charmed you will run toward the charmer at 3000mph like an idiot. Highlander enters cooldown upon casting, and with Presence of Mind it is possible for the duration of the ultimate to exceed the cooldown. If you use Highlander while Highlander is already active, if the remaining duration is below 7 seconds, it will refresh. If the remaining duration is above 7 seconds, nothing will change.

Summoner spells: Flash and Smite. Smite is self-explanatory for a jungler. I prefer Flash over Ghost because Yi's Highlander replaces it, and you might need the blink in order to get out of traps.
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Primary Runes

This is simply the best keystone for Master Yi. Synergizing with his AS-oriented kit, it both strengthens him and allows him to proc his AS-oriented kit more often.
This rune will make you extremely strong when you are building on-hit. As a stacking rune, it will work extremely well with Guinsoo’s.

This rune is the best rune for Master Yi in its tree. It provides great sustain in group fights and the 25 additional gold adds up when you end up having 20+ kills per game.
This is the best non-keystone rune for Master Yi. Free 18% attack speed by 15 minutes = enemy 15 minute surrender.
The best rune in its tree, this rune allows you to set up good ganks against low-health enemies and in general averages the highest damage output per game. Alternatively, against tanky teams, take Cut Down.

Secondary Runes

A great tank-buster, this is the best option for Master Yi in its tree. This can end up playing a huge role against tanky enemies.
This is a great rune that allows for early snowballing and sustain both in the jungle and in duels. The extra lifesteal really comes in handy.

Other Options

absolute This makes your clear better and gives you some early game damage. Whether you take sorcery or domination is a matter of preference.
Will allow you to scale even harder into late-game.

First Clear

The best starting items for Master Yi are Hunter's Machete and Refillable Potion. The clear path that I follow most often is blue - gromp - wolves - red - raptors - nearest scuddler - krugs. Yi can't clear raptors until level 3, when he gets his Meditate. However after 8.11 changes to jungle experience and clearing I rethought my strategy. In late-game enemy team comps, you might want to get red buff and then nearest scuddle, and then sit on that and try to make some plays in your red-side lane and mid. After ganking mid, go to the other scuddle and then get your blue cleats. Afterwards finish up with raptors and krugs. After clearing your camps, you should look for opportunities and maybe take the enemy jungler's krugs. Many junglers overlook taking scuddlers and krugs, but in reality they're both great sources of experience, and scuddlers are great sources of vision. The first five minutes should be spent farming. After five minutes, back and build either your Skirmisher's Sabre or start building your Essence Reaver. After getting both of your buffs and hitting level 6, be ready to rush drag. It is very important to have both of your buffs when you take drag. Although Master Yi can solo without the buffs, mana regen and damage increase will make the fight go faster and put less pressure on you. Ask your bot lane and mid lane to help. If a fight breaks out, don't worry. Master Yi has very strong group fights and you are most likely to win a 3v3 (or a 3v4 if your midlaner is there!). More on objectives later. After getting dragon and/or accumulating a lot of gold, back and build your Skirmisher's Sabre - Bloodrazor or complete Essence Reaver if you’re extremely fed already. This is when Master Yi gets his powerspike. Only once you have built your firstitem should you start fully committing to ganks.The next item to build is Berserker's Greaves. It gives him both MS and attack speed, making these the best boots choice for Yi in almost every scenario. More on items later.

Ganking

If you see a high-pressure lane matchup where both champions are at low health, rush up and help. This is a great opportunity to get a kill, because the enemy is likely to be playing more aggressively than if they were the only ones vulnerable. Keep in mind that the enemy jungler will also be coming up to get a kill. While you are coming toward the gank, pop your Highlander for more MS and AS. You do not need to Alpha Strike them because you are fast enough to catch them, especially if their lane is pushed in. Don't worry, you and your laner will do enough damage. If they Flash or use an escape spell, you can either keep chasing in the hope that you'll catch them or you can Q after them. Your Q has more range than the average escape spell, so it's important to save it. In the early game, be careful, as they may go under tower and you'll take major damage. Sometimes, your Highlander and Alpha Strike will not be enough and you will want to Flash (or if you built ER first item you can Q again and then again...). My recommendation is not to Flash after them unless you have a guaranteed kill on them (100 health left or so). You might need your Flash for more important situations.
Spend most of early game free-farming and looking for opportunities. A low-health enemy laner or a pushed in bot duo is a great chance to get a kill or two. However, when you see a group fight break out, you should run in and initiate. (Only do this PRE-15 minutes). Yi's Alpha Strike makes him an amazing group fighter, and his high natural AD output along with his Wuju Style puts him at an advantage over other hypercarries.

Early Items

Skirmisher's Sabre is your most important early item. Red smite gives you some solid duelist power, and later it will build into Skirmisher's Sabre - Bloodrazor which is your strongest early-game item.

B. F. Sword is a standard early item for any hypercarry. Providing nice AD on its own, it will later build into Essence Reaver or Infinity Edge providing for a huge powerspike.

Zeal is another crit core early item that should be built. Later building into Phantom Dancer or Statikk Shiv, your Zeal item provides for another mad powerspike when paired with Infinity Edge. The on-hit equivalent of this item is Recurve Bow.

Remember: Master Yi is a late game scaler. His powerspike happens when he builds his fourth item and hits level 11. During early game, your job is to make that late game powerspike happen as early as possible.

Middle game is probably the hardest stage of the game for Master Yi players. Most champions get a second item powerspike, but Yi doesn't get it until he builds both Infinity Edge and Phantom Dancer. During midgame, one of the most important things to do is continue farming. If you see a stagnant tower-sieging lane, where both sides are equal, let it stay that way. Do NOT run in unless you have a Sion or Malphite who's going to peel and give you a triple kill on the spot. The best thing you can do, both for yourself and for your team, is to rack up 1-2k gold from yours and your enemy jungler's camps and THEN run in with both of your core items.

Team fighting is one of the simplest aspects of Master Yi. Your Highlander passive allows you to literally spam Alpha Strike over and over again. Remember, do NOT engage alone (I mean, if you're 19/2 and level 17 by 15 minutes then I guess you can unassisted penta, but in realistic situations) and wait for your tank/engage to go in. Your job is to CARRY and if that means you play safe, even if your team wants you to be aggressive, then that's what you should do. Do whatever you need to do to go full build.

A Master Yi who has scaled properly into late game is practically unstoppable. The only champions who can really stop Master Yi in endgame without a significant gold lead are Nasus Illaoi Darius Tryndamere and Garen because of their survivability and insane potential damage output in late game. Master Yi can pretty much 1v1 or even 1v2 any squishy target at almost any point in the game, and late game is no different. In group fights you should target the enemy ADC and then the second squishiest target, whether that be the mid-laner or the support. Being able to play the role of an assassin with your Highlander and Alpha Strike is very important. Running in, two shotting the enemy carry and then the next squishy will turn the game around.

Securing natural objectives is one of your main jobs as a jungler. And being one of the most solo-queue oriented champions, as Master Yi you should do the most you can to at least get buffs for your team.

Dragons
There are four types of dragons. The Cloud Drake grants extra movement speed, the Infernal Drake grants percent AD and AP, the Mountain Drake increases your damage to objectives, and the Ocean drake increases your out of combat regeneration.

Being able to secure these buffs will greatly strengthen your team, and even losing a few kills for a permanent buff is well worth it.

Out of all the dragons, mountain drake is the easiest. Mountain drake deals the least damage, and technically, you can solo it at level three with both buffs. If mountain drake is the first spawn, there won't be an early fight for it. People are likely still establishing laning pressure and this isn't a buff as valuable as infernal or ocean (or at least the enemy won't think it is!). Soloing this might be too risky, as it will take you 30+ seconds and if the enemy jungler comes you're gone. But if you remove all vision, make it look like your bot lane backed, and secured rift scuddler, you can let bot and/or mid sacrifice a little bit of experience and laning pressure for an early dragon.

How to prepare for an early (pre-level 5) mountain drake:

1. Pop vision plant in the enemy jungle.
2. Place a Control Ward in drake pit and buy Oracle Lens. Do NOT destroy any wards in the pit as that is basically a message saying "I am here" to the enemy team.
3. Secure the rift scuddler in the river.
4. Have your top lane push in to attract a top-side gank.
5. Make it look like your mid and bot lanes are recalling. Make sure the enemy SEES you "recalling": have the laners stand behind tower and recall when the enemy lane pushes in. When your lane pushes the enemy back out of tower range, your laner should go around through your jungle and toward dragon.
6. Early 4-man dragon, if a group fight breaks out, destroy wards and have your top-laner Teleport down.
7. Smite the dragon when it's at enough health to die from smite. Do not start unless your smite is up or will be up in 5-7 seconds. I can't count how many objectives I've stolen playing against new junglers who don't Smite objectives.

These rules apply mainly for early dragon rushes, but these general guidelines also work for infernal, cloud, and ocean dragons after level 6. When to rush those dragons?

1. Pop the enemy vision plant.
2. Control ward dragon pit: again, don't destroy enemy wards.
3. Secure rift scuddler.
4. Make sure your top-laner is ready to teleport down.
5. Once you have started dragon ask top-laner to teleport down and destroy all enemy structures so that they can't teleport.
6. If you feel endangered, do not start dragon unless the enemy mid-laner or bot-laners have backed. Once they back start immediately or you will lose your 5-man powerplay.
7. If all enemy laners are in place, and you have no vision on the enemy jungler, have your top-laner teleport down, destroy all wards, and get ready for a fight. It will be a 4v5. You should solo drag, while your top and support guard your pit and your carries backline.

Following these steps you should easily secure the first dragon. If the enemy gets first drag, don't stress, just make sure to solo a few later on. You will be surprised how the buffs accumulate. Infernal will strengthen your damage output by tons, and Cloud will make you better in group fights, being able to take poke and instantly regen it. Those two are probably the most important dragons.

Late in the game, when the Elder Dragon spawns, make sure to secure it ASAP. The 3-minute powerplay will strengthen your group fighting and will increase your objective securing power. It can even win you a game.

Rift Herald
Unfortunately, Rift Herald is overlooked by so many newer junglers. Herald is a one-time monster that spawns in baron pit at 10 minutes and disappears at 20. Rift Herald drops the eye of the herald, which grants a buff to the wearer and allows you to summon the Rift Herald to assist you. Once summoned, the Rift Herald will siege enemy towers, doing thousands of damage to turrets with one hit. Obviously, the Herald is a very important objective.

How to prepare for Herald:
1. Secure top-side scuddler.
2. Control Ward the pit: if any wards are revealed, do not destroy them as it will reveal your intentions.
3. Pop enemy sight plant.
4. Keep enemy bot/jungler busy. Have your bottom lane push in and make it look like you are going for dragon. A nice addition would be to gank bot prior, so it appears that you're botside. This will attract the enemy jungler to bot-side and you will get a free herald powerplay.
5. Like with dragons, make it look like your top and mid-laners are recalling, and then have them come to Herald through your jungle. Another option would be to let them back and then have them Teleport to pit.
6. Keep Oracle Lens up while capturing Herald.
7. Smite this. This is definitely the most important early-game buff, and getting it stolen would be disastrous.

Following these steps will increase your chances of capturing Rift Herald and ultimately will grant you a tower or two for free. Rift Herald is very susceptible to damage from behind, so when he charges at you, attack him from behind for massive damage.

It is common courtesy to let your top-laner capture Herald. It will strengthen his split-pushing potential, especially if you're group fighting in another lane, and the empowered recall granted by capturing the Eye of the Herald will allow him to get out of a lane quickly if he's about to be collapsed on.

Baron Nashor
Baron is arguably the most important buff in the game. The buff granted increases your team's recall speed, increases your base stats, and enhances lane minions while you are close to them. The buff is lost upon death. This means that this buff will be highly contested and securing it can almost win the game for you.

Preparing for Baron is one of your most important tasks after 25 minutes. Because it is such an important buff, the enemy will almost always be trying to rush a Baron the second they get an advantage.

Good times to rush Baron:
1. If the enemy top-laner Teleport is down and they're split pushing bot, if you can get your whole team on Baron, you're likely to get it.
2. If you know your group fighting is stronger than the enemy's, then feel free to start Baron comfortably. However, use good judgement: if it's 30 minutes in and the enemy has a 30/2 Twitch then you shouldn't risk it.
3. With an advantage in numbers. Send your team assassin on the prowl, have them catch out an enemy: turn a 5v5 map into a 5v4. Similarly, after an ace, if you have 3+ players, rush a Baron.
4. After pushing in a minion wave. If you just got an inhib and the super minion wave is plowing into the enemy base, the enemy has a choice: either contest Baron or lose a Nexus Turret. The choice most players will make is obvious.

You will not always have these dynamic advantages that have "Free Baron" written all over them. Sometimes, you will have to stick with a gold or a vision advantage.

How to prepare for a 5v5 Baron:
1. Push in your waves. If the enemy is distracted, trying to protect inhibitor towers, then they will have less time and less people contesting Baron. Even if they contest, you are likely to get a free tower.
2. Remove enemy vision. Keep baron pit Control Warded and use your Oracle Lens during a Baron fight to prevent enemy vision.
3. Pop nearby blast cone. A team death is worth a Baron. If the enemy suicides but steals Baron, you are down on the exchange unless you can win the game before they're back up. Do NOT let this blast-cone behind Baron pit ruin a game for you.
4. Pop nearby sightstone plants. Even use them to remove enemy wards from Baron pit if necessary.
5. Secure Rift Scuddler for extra river vision.
6. Stealth ward around river. Make sure all river entrances are warded, so you are ready for any ambush.
7. Time your Smites. Let your tank take Baron aggro so you don't have to smite for health. Make sure you Smite kill this objective.

Following these guidelines you should be able to secure a Baron for yourself and for your team. Similarly, if you see the enemy preparing for Baron, do anything you can to show them that you can contest the buff. Sometimes, you should even bluff. For example, if you remove enemy vision and there are only 3 of your team members there, if the enemy has no vision on the other two members of the team they could be worried that all five are there. Meanwhile, the other two could get a dragon or get to the Baron pit for a real stand-off.

Because your entire kit synergizes around AS, it is best to build attack speed/AD items.

Bloodrazor This is your core item on Master Yi. The first item you should try to build, this item gives you your first powerspike.
Essence Reaver It turns out that giving your champion 8 seconds of Urf mode makes them pretty damn strong. This is the ultimate one team powerspike. It is so strong that you might almost want to rush it BEFORE bloodrazor to get those good ganks in. The only issue? It’s quite the payout, and the sheer cost makes me discourage you from buying it before maxing your jungle item. Being able to have a perma-E up and spamming Q every 3 seconds will guarantee you kills almost al the time. Rip weak early game yi- building this items will make him a hypercarry at level 6.

Berserker's Greaves A great early-game item, you should build this item somewhere in between or parallel to your jungling item and Infinity Edge. Providing for a nice amount of AS and mobility, boots are always a great early item to build.
Infinity Edge Another staple item on Master Yi, this item provides solid increase in AD and greatly strengthens your damage output.
Phantom Dancer Master Yi gets his second powerspike when he builds IE with PD. Rush this item with Infinity Edge. Providing for nice amounts of crit, AS, and survivability, this is another core item in your build.
Blade of the Ruined King A great tank-shredder, this balanced item is a good choice to have on Master Yi. Although not a core, it's always a nice item to build for more sustain, AS, and crowd control on its active.
Guardian Angel This is a great second chance in group fights. With a lot of late-game power, this could be a good finish-up to your build if it's a close game.
Youmuu's Ghostblade More mobility, more tank shred, more damage output: what's not to like? In some scenarios, this item is a great tool to have. Against tanky or high-CC enemy teams, I would take this over GA.
Statikk Shiv Some people consider this a staple item, but I consider it optional. If you need 100% crit then go ahead and take this item. This is a good item against squishies: you will literally one-shot enemy ADC with a full build with this item. However, against tanks, there are better options.
Dead Man's Plate If the enemy carry is really fed, this item is something you should build. Giving more mobility and nice damage output for a tank item, this is a nice situational item.
Guinsoo's Rageblade A great item to buy if you are ahead, this can be a little bit of a risk if you're behind. It accounts for a mad early-game powerspike, but its late game relevance is debatable. Going into a full Guinsoo's build is great against hard AP and tank teams. This item has particularly good synergy with Blade of the Ruined King because it will double-proc the 8% passive.
Lord Dominik's Regards This is a nice choice against very powerful enemy tanks. With a huge damage boost against higher max-health enemies, this is a good situational item.
Mercurial Scimitar I recommend this item against high-CC enemies. Although simple slows will not work on you because of your ultimate, those 10-second CC's like Morgana's Q can be game-changing.
Wit's End A situational item, this is both a good offensive and defensive item. With good tank-shredding on it's passive, this item synergizes very will with any mage teammates or magic damage on your team. It also works very well with Guinsoo's Rageblade.
Death's Dance This is a very strong item on Yi after the recent change which makes you heal for ALL damage dealt. On-hit Yi build deals about 25% true, 30% magic, and 45% physical damage, which means you heal a ridiculous amount as well as survive pretty well against bursty enemies.
Sterak's Gage This item is very good if you need survivability other than Death's Dance. However, the two items have bad synergy, so I don't recommend building both.

As promised, here is the chapter in which the two builds are contrasted.

The core Crit build consists of Infinity Edge Statikk Shiv and Phantom Dancer.
Pros of Crit Build
1. Strong burst damage. The energized attack proc will deal very high damage, and with this build you will be able to assassinate enemy squishies very easily.
2. Good wave-clear. Energized attacks are very good at wave-clearing, and you will easily be able to one-shot enemy minions and escalate your late-game build.
3. Safe. When in doubt, build crit. It is generally the safest build to go by, as it is always a solid choice, and you will easily be able to kill anyone unless they are building full armor.

Cons of Crit Build
1. Expensive! Infinity Edge is quite a pricey item, and building two Zeal upgrades might just take a very long time.
2. Vulnerable to tank items. This is not a tank-shredding build. Tanks who build Randuin's Omen or Thornmail onto you will be a huge problem: with this build you have nothing special going against champions with powerful defensive stats.
3. No defensive stats. Unlike the on-hit build, with crit build you have zero defensive stats, no sustain and no resistances. Make sure to be careful against fed enemies.

The core on-hit build (I prefer this one) consists of Skirmisher's Sabre - Bloodrazor Blade of the Ruined King Wit's End and Guinsoo's Rageblade.
Pros of Guinsoo's Build
1. Huge tank-shredding value. Both BotRK and your full jungle item do %health damage: BotRK does 8% of current and jungle item does 4% of max as magic damage. Paired with Wit's End which steals MR from the enemy, that damage can become unresistable. With a fully stacked rageblade, you could be doing up to 24% of the target's health in one hit. Of course, if the enemy is an ADC who will die from one energized attack this isn't worth it, but if the enemy team consists of 4 beefy champions and a carry then this is a worth-while investment.
2. Cheap! This build is much cheaper than the standard crit build. Rageblade is cheaper than IE, and your jungling item and Wit's End are both cheaper than the upgraded Zeal items.
3. Solid defensive stats. Wit's End grants you a ton of MR, and Blade of the Ruined King grants you lifesteal and CC: what more could a hypercarry want?

Cons of Guinsoo's Build
1. Requires setup. This build has zero burst. You can't just go into a fight without a prep and get a 1v5 penta- that's just not his this build works. To be fully effective, you need to fully stack your rageblade before entering group fights.
2. Situational. Against squishy AD enemy teams, there is no reason to build this. You will have much more luck with a bursty offensive crit build than with a slow-starting tank-shredder build.
3. Weak early game. Unlike the crit build which provides consistent DPS, a single rageblade will not do you good as it will on champions like Kog'Maw or Varus. For a fully effective rageblade, you need Wit's End and Blade of the Ruined King.

Here are the factoids for each build. The choice is yours: I hope you make the right choice for each game.

Immobile ADC's Immobile ADC's provide absolutely no threat to you, even if they have a high gold advantage. Their only option would be to kite you with the small amount of crowd control they have (slows like on MF's or Varus's E), but your Highlander negates all slow affects. You can catch them easily and chunk their health down from 100 to 0 in seconds.

Medic Supports There is really nothing that medic supports can do to stop you from killing their ADC. Your sustained and burst DPS is too high for the support's heals, and unless they land insane amounts of CC (stuns or roots that last for a long time) then you will easily be able to take out the ADC and the support in just a couple of hits. Just get as close as possible, and dodge the CC with your Alpha Strike.

Hook/Pull Champions The point of a hook/pull champion is to single out an enemy and so to speak assassinate them. They are highly reliant on their team, and champions who can escape well and/or evade attacks are a great counter. Think of these hooks as a free engage. When hooked, immediately engage with your Q. It will output damage and you will evade over half of the burst combo that usually follows the hook. If you are alone, still use your Q. Sometimes you will have to use Highlander or even Flash to escape, but most of the time you will be able to kill the enemy ADC and even end up with a double kill.

CC/Tank Engagers Similarly to hook champions, CC initiators provide pretty much a free engage for your group fights. They are an easy target for you to gank in lane, and if they start a group fight, you can just turn it around by using your Alpha Strike to evade the first follow-up and then assassinate the carries.

Mobile Marksmen Mobile ADC's provide slightly more of an annoyance than immobile ones do. It will be a bit harder to pull off ganks if the ADC can just dash/jump under tower early on. In late game, however, if you catch the ADC out alone, you can easily catch them with your Highlander. They will try to kite you, but you are faster and can kill them very quickly. The secret with killing them is getting close: but if you are low on health do not chase them as they will probably kill you first.

Hypercarries Hypercarries are champions who scale hard into late game. When paired with strong engage-tanks, these are quite the threat. Against hypercarries play as safe as possible. Assassin hypercarries can burst you down extremely quickly, and bruisers will be able to CC you and then kill you. Do not engage 1v1 unless you have a significant gold lead. Generally, hypercarries are more of a threat to your team than to you, but they are still quite dangerous.

CC Tank Supports While not a problem on their own, they are a threat to be reckoned with if paired with a marksman. With powerful engage and disengage tools, tanks are currently the strongest supports. Be wary of going against a tank support: this is not a squishy botlane who you can easily 1v2. Their beefiness will allow them to peel for the ADC without dying, and while you can still 1v2 them in some situations generally be very careful until late game.

CC/Combo Mages Just like mobile ADC's, the secret to beating these guys is getting close immediately. Almost all mages have some source of crowd control, whether it be a slow, a stun, a root, or anything in between. If you fail to dodge this source of CC you are good as dead: these mages can burst you down very quickly. However, once you dodge the CC and engage them with Alpha Strike, that's 300 gold for free.

Early Game Duelists Early game duelists are the biggest problem for most hypercarries. These champions get in the way of farming and can scale hard if they get an edge over you early on. How to beat them? Keep your jungle warded and free farm as usual. They will often invade you, and there's very little that can be done to stop that. However, you can maintain good vision and hopefully you will be able to collapse when they invade.

Juggernauts What can I say? They are annoying for everyone. If a Nasus goes into late game with 1000 stacks on his Q there's no stopping him. So? Don't let him get 1000 stacks. When you're up against a juggernaut, the only thing you can do is stay on their side of the map and gank as often as possible. With the help of your laner, you should accelerate your late game build and be able to win the game before the enemy scales hard enough to shut you down.

Assassins Because of Yi's natural squishiness, he becomes a great, juicy target for assassins. Once the combo starts, the only way to stop it is to initially Meditate followed up with an Alpha Strike to dodge a few abilities. Almost every assassin will be able to burst you down 100/0 within seconds, and your only chance is to kill them before that happens. This is one of the times where you must use your spells defensively, otherwise you will be dead before you know it.

Hypercarries Master Yi should not be your pick if your team has another hypercarry on it. Much more valuable would be if you played a high-CC early game jungler, or if your laner played a group fight initiator. With two hypercarries on the team you will both be competing for kills and hindering each others' progression.

Juggernauts Similarly to hypercarries, playing with late-game juggernauts will hinder both you and the juggernaut's progression. Ganking won't be effective in the early game, and you will likely fall behind in the early game.

Medics Although medics provide comfort in poorly organized ganks, they have very little relevance after laning phase. You really don't need heals except for very few situations, and you would benefit much more from a tank support

CC-heavy Marksmen Marksmen with CC are great. Although they have no particular synergy with Master Yi a well timed set of roots from an ADC can get a great fight going.

CC/Tank Supports Although better than medic supports, these champions still do not fully provide for your needs. These champions can engage decently well and can keep you alive after a blunder, but they will not turn a group fight fully in your favor unless something unexpected happens.

Assassins These champions also do not have particular synergies with Master Yi. However, if your bot lane is struggling, these champions can easily roam down and pull off a successful gank. This allows you to stay top-side and/or keep farming freely in your jungle or even invade your enemy while they're busy covering up another lane.

AoE/CC Mages One of the best teammates you can get is an AoE and/or CC mage. A champion who can land an AoE stun acts as an engager for you, giving you that much more time to deal all the damage you can to the enemy team. A powerful mage can turn a fight around for you.

Tanky Initiators A hypercarry's best friends, these champions literally set up 2v5 pentakills for you. Make brave plays with them, and treat them as an ADC would treat a support. Respect your engager, they will make your group fights good.

Hook/Pull Champions These are simple. If they pull someone and pull off a good CC combo, the next group fight becomes either a 5v4, or the enemy team will follow up. Treat enemy follow-ups as a free engage and do your magic.

I hope you enjoyed reading this guide. If you have any suggestions or questions, feel free to leave a comment. Good luck and have fun playing Yi!