I'm a season 1 player and I have a decade long history of playing Master Yi as an OTP. While I'm not a Challenger player or the best Master Yi player in history (that title is for Cowsep), I've been in all phases Yi has been in, and it was very pleasurable playing this champion. I mainly play him as a jungler assassin or a top lane assassin. While I have tried off-tank Yi, it really doesn't fit Yi's playstyle. If you want off-tank Yi, play Jax instead.

Master Yi has always been a champion that went into team fights and destroyed anyone in his path and got pentakills. Whether it be AP or AD yi, this has always stayed the same. Yi is an excellent dueler and a damage dealer, with potentially the most amount of DPS a champion can wish for, along with all the utilities of an assassin.

Master Yi is a very squishy champion. Once he gets hit by damaging skills or gets crowd controlled, it is hilariously easy to kill a Yi. For this reason, this guide incorporates a few defensive items to fill in that gap for him.

His passive, Double Strike lets him double strike every 4th attack. 3 attacks, 1 double-attack, 2 attacks, 1 double-attack, 2 attacks, 1 double-attack etc. Guinsoo's Rageblade empowers this skill to another level, by making him double-attack every other attack. 3 attacks, 1 double-attack, 1 attack, 1 double-attack, 1 attack, 1 double-attack... This is the first reason why he's the best Guinsoo's user.

His Q, Alpha Strike is one of the most broken skills in the game. Master Yi excels at dodging skills with his Q. It makes him untargetable (not invulnerable!) for a short duration and blinks you to a target position, all while dealing damage. It serves both as an engage and disengage tool (using minions).

His W, Meditate is a healing skill that also reduces the damage taken. I can't overstate how powerful 2nd level W is. Compared to level 1, it heals almost twice the health. He can use this skill to medibait people. It is a channeling ability, so enemies can cancel it by crowd controlling him. Most of the time, he will be using Meditate to do an auto-attack reset to hit faster.

His E, Wuju Style is as simple as a skill can get. True damage on-hit. This is the second reason why Master Yi is the best Guinsoo's user. This skill lets you melt any tank in the game without effort.

His ultimate, Highlander is the bread and butter of Yi. The passive lets him spam his basic skills as he gets more kills, making him an excellent reset champion. He can utilize the active to chase kills, get in Q range, get away from chasers, get baron quicker etc.

Master Yi's itemization primarily focuses on attack speed, on-hit effects, attack damage, or critical strike chance/damage. Secondarily, he can go for health, resistances, tenacity, life-steal, or lethality.

Master Yi is very strong with finished items like Guinsoo's Rageblade, rather than components like Pickaxe or Recurve Bow. That's why I (and Cowsep) recommends selling tier 1 boots, or excess daggers to finish items earlier, or buy a cheaper alternative if you can finish one but can't finish the other.

Because Master Yi lacks in the defense department, you will usually see him with at least 1 defensive/off-tank item in every match. This gives him the survivability push he needs to tank a few random stray bullets in teamfights, and get all the kills. Such items usually grant on-hit effects or attack damage to supply his strength while being a defensive item.

It really doesn't matter. Master Yi is (currently) weak early-game, and unlocks his potential at level 6 / first item. Until that point, Master Yi mostly avoids duels and tries farming, be it in lane or in the jungle. After he is level 6, as a jungler he can gank lanes to get kills and snowball, or as a laner he can get prio and roam other lanes, help his jungler get objectives or destroy his opponent and obliterate towers. You will mostly be collecting kills and snowballing.

As a Master Yi, you need to pick your fights. Your first and foremost goal is to get stronger yourself, snowball, and destroy your enemy. To achieve that, a crucial second goal is not feed your enemy big shutdowns. As a hypercarry, you'll spend most of your games with a big bounty on your head. Feeding that to your opponent will not only put you behind, but give the enemy chance to recover and prevent you from snowballing. For that reason, try to pick fights that you have guaranteed kills and you can get away with without giving big bounties/losing objectives.

Lets consider a specific case like this: you are going 7/0 as a jungler, and you have a 550 gold bounty on your head. Your allies are dead/not paying attention/far away, and there are 3 averagely fed champions with high damage output killing the dragon, at around 60-70% hp. You may think you are guaranteed to get at least one kill, and steal the dragon, and carry the game, and your teammates will praise you for your hard work, and get 4 honors in the end game lobby. But in reality, what happens is that you go in 1v3, fail to steal the dragon because your smite was down/you mistimed the smite/couldn't coordinate smite damage with Q damage/your cursor was on the enemy to attack, and then you maybe get a kill and you die. You lose the objective. You lose your dragonside jungle. Enemy carry gets 850 gold, finishes their item. Enemy jungler finishes their item with the gold they earned from your dragonside camps. In the next fight, you misjudge their power. You get one shot. You ragequit.

For that to not happen, you should learn to pick your fights, and give up that dragon, and rotate your other side of the jungle. You lose the objective, enemy carry stays weak. Maybe there was a free kill on the other side, who knows? You get stronger either way, you one shot the enemy next fight, enemy ragequits.

Lets consider another case for the laner. You are a 3/1 as a top laner, and you have a 150 gold bounty on your head. You just killed your opponent in the river and there is a jungler Kha'Zix pushing your tower. You think you can win the 1v1. You go all in with your Flash + E + Q + W, you couldn't kill him because you didn't have Highlander. Kha'Zix escapes into his red jungle. You chase after him, not being able to catch up to him. At around his krugs, your opponent surprises you from the bush, and you die 1v2 because Kha'Zix has his Isolation passive. You feed a bounty to Kha'Zix. Your opponent gets plates/tower. Kha'Zix ganks you again, killing you 1v2. Your jungler question marks you. You ragequit.

For that case to not happen, you should pick your fights, and not engage in fights you don't think you can win. You may be able to kill the Kha'Zix, but you won't be able to chase after that Kha'Zix without your ultimate or Q up (if you used it for engage), because he has his leap and ultimate movement speed bonuses. Instead, you should clear the wave, try killing him, but don't chase away into his jungle where your opponent is going to be coming back from. Or you could freeze the lane until your opponent comes back and not get Isolated by Kha'Zix near your minions, your choice. You get the minions, don't feed Kha'Zix anything, don't feed your opponent an assist, or plates/tower. You stay ahead. You destroy your opponent. You 1v2 your opponent and the Kha'Zix. Your enemies ragequit.

Laning with Master Yi is easy, as your main DPS comes from your auto attacks, and you can utilize that to farm minions as fast as you can. He has high base movement speed, so you can sometimes outrun an enemy jungler coming to gank you. Thanks to his extremely high damage output, you can potentially 1v2 the top laner and the jungler too.

Master Yi is generally weak against ranged champions, champions with a lot of CC, or burst damage dealers. You will need to either go all in and destroy your opponent in one go, or play it safe and farm minions. Most of the time, you can't trade without either you or your enemy dying. The reason for this is that Master Yi mainly uses Q as an engage tool, and can't reset it properly without getting kills. If you have used it as an engage tool, you won't have it available for disengages. That's why you'll either be sitting ducks near your enemy or won't be utilizing your Q to engage (missing out on big damage/dodge).

Once you get your first item (Blade of the Ruined King, Guinsoo's Rageblade, Kraken Slayer, whichever is cheaper at the time you recall), you can confidently duel your opponent and win (if it's not a hard counter). No, Teemo is not a hard counter.

For On-Hit Master Yi:

Red -> Krugs -> Raptors -> Wolves -> Gromp -> Blue -> Scuttle, you're free

For Krit Master Yi:

Due to the high gold requirement of the B.F. Sword, you should consider this rotation to buy it after your first recall.

Raptors -> Krugs -> Red -> Wolves -> Gromp -> Blue -> Scuttle -> Raptors, recall, you're free

Jungling with Master Yi is a bit more convoluted than laning, because you have twice the map pressure and your teammates mostly expect you to help them get stronger, but you have to get stronger yourself. Master Yi is a snowball champion, and can't really play from behind. So you have to visit a lot of lanes, get a lot of kills, and finish the game before your enemies catch up.

In the early game, you're weak, so you'll almost always go for a full clear in your jungle. Once you're level 4, you can contest scuttle, go for a gank in any lane ONLY TO PICK UP KILLS, never go for a gank unless you think you'll be able to beat everyone by yourself or with little help.

After recalling, try going to the side of the map that you think a teamfight will break in the next few minutes. This could be a dragon, voidgrubs, botlane, etc. In the upcoming fight, you will make your first big decision of picking your fights. Your main goal is to snowball, not to get the objective at all costs. Don't be afraid to give up objectives. If you think you can't contest the objective by yourself or even with the help of your allies, give it up and rotate towards the other side of the jungle. There are free camps waiting for you there.

Mainly focus on farming your jungle camps and never let the enemy jungler counter jungle you. If you die while ganking a lane/taking an objective with your jungle camps up on that side of the map, expect those camps to be gone when you spawn. Even if they aren't, they should be, and it is a mistake of the enemy jungler to not punish you. Don't rely on your enemies making mistakes. Never give them the chance to begin with. This rule applies to the whole game, early, mid or late.

If you hit the first hit of a Double Strike, you don't need your character to stop moving for the second attack (unlike an ability like Jayce's W or Ashe's Q). You can kite like you're doing normal attacks all throughout. The second attack has a slight delay based on your attack speed. It applies on-hit effects with full effectiveness, but deals half the base damage. It can critically strike with half the damage.

Master Yi's passive gives him status effects with a grayscale image of the passive and a saturated image of the passive. The timer running out of the grayscale status effect won't reset your auto attack timer. However, the timer running out of the saturated (green) status effect (meaning your next strike will double strike) will reset your auto attack timer, potentially making you cancel that attack unconsciously. This happens often while clearing the jungle.

Master Yi can dodge skills aimed at him using his Q, which gives him untargetability momentarily. In the past, this skill used to have a slight delay (with the duration of an attack animation), but nowadays, it makes you untargetable instantly. You can use it to dodge Karthus ultimate, Teemo darts, Veigar ultimates, Lulu polymorph, targeted skills like Pantheon stun etc. While Master Yi can still enter his untargetability immediately after being stunned by something like a Renekton W, he will exit Alpha Strike in a stunned state.

Master Yi can appear in any location a short perimeter around the first attack target of Alpha Strike. You can appear in front of a Rammus to immediately end his Q, appear behind a Nunu to dodge the snowball etc. You can utilize this to appear towards the location the enemy is escaping towards to get the range for that one last auto attack. Though, it is very predictable where you'll exit Alpha Strike if you do this, and enemies can pre-fire skills towards your exit point.

You can use Alpha Strike and Double Strike together by hitting the first attack of the Double Strike and Alpha Striking before the second strike animation begins. The second strike will still hit, apply all on-hit effects at full effectiveness etc. It will appear as if you had auto attacked your target while untargetable.

Alpha Strike used to hit every target only once and it would end early. Nowadays, you can hit one target multiple times to deal more damage. In my first jungle clear, I prefer using Alpha Strike on the nearest raptor when I'm coming from krugs to hit 4 raptorlings.

Master Yi's Meditate reduces the damage taken for the whole duration. There used to be a bug where using Meditate and canceling it right away right before taking a turret shot would reduce the damage more than it should've. Nowadays it has been fixed. For the first 0.75 seconds of Meditate, your damage reduction is way higher. So you can use it as a momentary damage reduction to tank a single spell like Veigar Ultimate, or turret shots.

Master Yi's Meditate can be cancelled as soon as it starts, and it resets the attack timer. You can do auto-attack resets using Meditate to clear your jungle faster, or get that last auto attack on that one low hp enemy, or deal way more burst damage using Hail of Blades (it gives you 1 more attack with extreme attack speed for every auto attack reset you do, including titanic hydra active).

While Master Yi's meditate gives Yi passive stacks and lengthens its duration, if cast too late it will cause you to reset your passive stacks. This does not happen with the E timer or the ultimate timer.

Master Yi's Wuju Style used to give a passive bonus to Master Yi's AD while its active was available. Nowadays this functionality has been lost. Your E timer is paused when you're in Alpha Strike or Meditate, so you can utilize those skills to squeeze out that last true damage out of your E. Activating Wuju Style won't cancel your auto attack, nor will it reset the attack timer. You can use it right before your first hit connects to maximize timer usage, though this is a bit risky move when you have high attack speed.

Master Yi's ultimate timer gets increased every time he gets a kill/assist. After an ace with 5 kills, you'll get a super long highlander enough to get you to baron and maybe get it midway. The timer is paused when you're in Alpha strike or Meditate, so you can squeeze out that last attack with a higher attack speed from your highlander OR you can Medibait people without comprimising your ultimate timer.