Hello Summoners! My name is Dalmond and this is my AP Master Yi guide. Recently I have been seeing more and more people playing Master Yi as an AP Mid or AP bot carry. It occurs to me that many people do well as AP Yi early game and end up falling off in the late game. In this guide I hope to correct this and allow Master Yi players to dominate as AP Yi throughout the whole game.
This is one of my first builds eva so if you have a suggestion as to how to make it better, feel free to drop a comment and maybe i'll read it and give you credit, etc., etc. If you rate it, leave a comment as well and let me know how ya did!
Hope you enjoy the guide!

Pros:

+ Great early game harass with Alpha Strike
+ Easy farming all game
+ Good amount of damage early to late game
+ Getting kills while using Highlander CD's all abilities
+ Is almost invincible late game while using Meditate
+ Makes squishies QQ all game


Cons:

- Very susceptible to CC
- Tends to have a bad late game if not fed
- Very item dependent
- Using alpha strike puts you right into the middle of a fight
- Must be patient in team fights to get kills
- Gets called a Ks'r by teammates (QQ)

Runes are set up so that you have a good amount of early AP and some magic penetration as well as resistances suitable to your lane. For the mid lane I use Greater Glyph of Magic Resist and for the bot lane I use Greater Seal of Armor. The reason I use Greater Quintessence of Ability Power is because I would rather have a lot more ability power early game so I can deal more damage with alpha strike. Now if you want Greater Quintessence of Magic Penetration for late game then get those. Do this, especially when you don't plan on buying any late game magic pen.

Masteries are set up as 21-9-0 taking all major AP masteries in the Offensive Tree and depending on what lane you're in, the appropriate defensive masteries. I take a point in Summoner's Wrath and in Summoner's Resolve to get the bonuses on both Ignite and Cleanse. For the bottom lane masteries, I anticipated much more harass from enemy champs since most bot lanes are AD carry + support. Due to this, I took three points in Vigor for a little more health regen in lane phase.

Double Strike - This is useful mostly to an AD Master Yi , however, it is still useful for AP Yi because his base damage is high enough to hurt early to mid game and coupled with a Lich Bane proc late game, his passive will help to deal even more damage.

Alpha Strike - This is AP Yi's bread and butter. It also allows Master Yi to farm like no other thanks to it's Madred's Razors-type bonus damage. The AP ratio on Alpha Strike is 1-to-1 so your total ability power is added as bonus damage. It is also a multi-target attack that can hit up to four enemies for the same amount of damage. As his only built-in source of magic damage, you need to be patient in battles as to when to use it. If you jump in too soon with it you will be CC'd down and most likely killed, so stay back and wait for the opportune moment to strike. Because this is Yi's only magic based attack, I strongly recommend a Deathfire Grasp so that you can do additional damage to an enemy in team fights or 1v1.

Meditate - This is what makes AP Master Yi overpowered and makes the enemy team rage and focus you in fights. Why you ask? Because if they don't focus you, you can go heal and come back to battle with full health before they even notice you were gone! This ability also scales well with your ability power, so the more AP the more healing you get! Not only this but at level 5, it gives you 300 bonus Armor and Magic Resist on top of what you already have! With this build, you will have over 400 MR and Armor while using Meditate. Use this ability if you are getting focused in team fights. Even their carry won't be able to damage you! Hopefully they will continue to focus you while the rest of your team slaughters their team. Watch out for enemy disables and knock-up/backs as those can disrupt Meditate.

Wuju Style - This ability is nice on AP Yi because it allows you to have some extra AD damage on your auto attacks while your Alpha Strike is on cooldown. Late game this ability is used to proc your Lich Bane after you have used Alpha Strike. Try to get your Double Strike at 7 stacks before using the Wuju Style Active. If you do this you can take more advantage of the bonus AD damage it gives, dealing double your bonus damage from Wuju Style! Unfortunately this does not proc the Lich Bane damage twice :P

Highlander - "Highlander too OP lol". This is what you'll say when you're chaining out Multi-kills due to the instant cooldowns you get from killing an enemy. This is like Tristana's Rocket Jump except it only works during Highlander and refreshes ALL cooldowns! With patience and practice you will dominate the other team because of Master Yi's ultimate. Without Highlander, AP Yi is not viable at all. The increase in movement and attack speed, while only secondary in purpose, makes for amazing escapes and chases. Couple his ultimate with a cleanse and you cannot be CC'd down during fights or while retreating.

Ok now for the Items. First let me say this: Building AP Yi can vary based on what the other team is building and as such you will need to build situationally. The items I've chosen for each lane is to counter what will most likely be in that lane. An AP carry at mid will warrant you to get some earlier magic resist whereas a AD carry in bot lane will warrant more armor, etc.

In my build I want to set up Master Yi to be able to do 3 things:

1. Do a ton of damage with his abilities
2. Be able to use his abilities more often
3. Have enough heath and resistances to stay alive in team fights

Item Progression

With those three things in mind, we want to be able to have a good amount of early game damage and cooldown reduction. For mid and bot lane I take Doran's Ring at the start. On my first back I want to be able to at least get my Boots and a Fiendish Codex. This will give my Yi not only some more ability power, but also mana-regen and 10% cooldown, which is a must have on alpha strike's long CD.

The core items are essentially the same: Rabadon's Deathcap, Rylai's Crystal Scepter, and Lich Bane. However the purchase order differs a little because our main focus in each lane is to not only build damage but to resist damage from our enemy in lane.

In mid lane, we want to counter any damage our AP carry counterpart is building, as well as, do some damage to them. An early Athene's Unholy Grail is a great item to do just that! This item is such a good item on Yi and I am glad Riot added it. In addition to damage and resistances it offers, it gives us great mana-regen which will allow us to be less dependent on blue buff and we can give it to our tank or support who could use it more.

I take Zhonya's Hourglass early if I'm laning bot against an AD carry or even top lane against a bruiser. The added armor and damage early game will give you sort of an OP advantage over your AD counterpart.

Why we build the Sheen next and eventually turn it into a Lich Bane should be a no-brainer, but for good measure I'll explain it in detail. Sheen's Unique Passive procs after Yi's next ability and does bonus Physical Damage equal to 100% of his base damage, which I think is his base attack damage. After you use Alpha Strike on an enemy, your next basic attack will do a lot more damage and helps you to secure a kill. It's later upgrade is Lich Bane and does then same thing Sheen does only better. Instead of base attack damage, it deals bonus physical damage equal to 100% of your ability power! That's right! At max build that's approximately 450-500 extra damage on top of Yi's already exceptional base and bonus attack damage from his E's passive! Lich Bane also offers 80 more ability power, +30 MR, 350 mana, and 7 movement speed multiplier. It's all round great item on AP Master Yi.

Item Explainations

Rabadon's Deathcap should explain itself. 140 ability power plus 30% of total amount of ability power. It's a core item for a reason, Do Not go without it!


Rylai's Crystal Scepter is here because it is essential to Yi's survival. The added health and ability power will help Yi stay in fights longer before having to retreat to Meditate. The Unique Passive slow on Rylai's will slow all enemy's hit by alpha strike by only 15% percent since it is a multi-target ability (not sure on this it's my assumption since it can hit multiple enemies). Even with the reduced slow, it's still nice and will help you and your team catch up to enemies.


Why take Ionian Boots of Lucidity over Mercury's Treads or Sorcerer's Shoes? Simply for the early CD's of course. If you really need the Merc Treads because the enemies CC is too much for just ]]Cleanse]] then by all mean get it. I usually trade out my boots later when I have CD from other items for either Merc or Sorcerer's for extra magic pen late game.


Along with nice armor and ability power, Zhonya's Hourglass has a kick *** active that will help take care of those pesky tower divers and junglers that come to gank you. When you're about to be dived or caught off guard by the enemy jungler, try to get under the tower and pop Zhonya's active. It may save your life :)


Deathfire Grasp is a good item on AP Yi because it gives you extra damage that can finish off low hp champs that are getting away and is also a good item to use at the beginning of a skirmish because it does more damage the more health the enemy has. It also reduces your cooldowns by 15% which is very helpful for an ability dependent champ like AP Master Yi. Keep in mind that you do NOT have to get this item if you don't want it.

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Some items I would suggest you use in place of Deathfire is either Abyssal Mask or Void Staff. Both items give you a good amount of AP. Abyssal gives you more MR with a Magic Resist Debuff Aura, Void Staff gives you +40% magic penetration. So which one's better? Well if the enemy team is stacking the hell out of MR (because they hate and fear you) and you don't have any other champions that deal magic damage on your team then get Void Staff. 40% Magic Pen doesn't add up as well if the enemy doesn't have a ton of MR to begin with. If it's the case that the team has a moderate amount of MR or no MR items at all and/or you do have teammates that do magic damage, then get Abyssal Mask instead. If the other team is more AD heavy, then skip these two and get Zhonya's Hourglass! If you need armor, GET IT!


Will of the Ancients is one of those situational items I was talking about. I do not think it is a necessary item on Master Yi, nor do I really think its a good item on AP Master Yi because he only does magic damage with Alpha Strike. However, there are cases where you should get WoTA. Specifically, if your team has 1 to 2 other AP champs on your team that would benefit from the spell vamp and have not yet bought WoTA, then I would say to get it. Now most of the time if its a champ that benefits from it, they will have already gotten it by then. Keep in mind, though, that if one of your teammates already has one, a second Will of the Ancients on you will stack with the other teammate's WoTA. Also keep in mind that the Aura spell vamp and ability power on WoTA ONLY stacks twice. So check to see if there is already two WoTA's on your team before buying.


Rod of Ages is an item I would try experimenting with and put in place of Rylai's Crystal Scepter. After it level's up to maximum stats, it gives you a little more health than Rylai's and a lot more mana to your mana pool. Gives the same ability power fully leveled up as Rylai's and it's also a little less gold. That and you get free health and mana back after each level up. The problem with this item is that it takes time to get it to its maximum stats, so you have to forgo some damage earlier on by buying Catalyst the Protector so that it will be at max stats before late game. Try it out and see if this works better for you.


Archangel's Staff is an item I wouldn't recommend on AP Master Yi. Sure it gives you a lot more mana and mana-regen, but it requires you have a spammable ability with a low cooldown in order to power up the item. Master Yi does not have said ability so I don't recommend it on him. In my opinion the 3% mana conversion to ability power is not worth the gold unless you plan to stack multiple Archangel's Staff on Master Yi. However, if you use this approach you will be a glass cannon and your teammates will most-likely call you a troll. You can experiment with it if you want but I don't recommend it.


Ah Mejai's Soulstealer! It's great item if you are dominating the competition, but I would only recommend it if you are confident in staying alive. Get this item if you are fed like a boss! Make sure you pair it with a Guardian Angel to protect those stacks! Have fun destroying the enemy team mwahahaha!


A Quicksilver Sash and Banshee's Veil Note*

If you'd like to troll the enemy team even harder with how much you cannot be CC'd, then place a QSS or BV at the end of your build. Don't be afraid to substitute some damage for a spell shield or extra cleanse if you are getting shut down because of CC. Having a Quicksilver Sash and a Cleanse is like slapping then enemy in the face and then spitting on them. Oh you CC me? Cleanse! Oh you somehow CC me again? Ha QSS! Later *****es, trolololol!!! Banshee's Veil can also give you more health and mana. If you can Alpha Strike in before they pop the shield it will save your butt from taking some damage or CC in a team fight.

SPACE

Master Yi in general is very susceptible to Crowd Control. Especially stuns and snares that can shut him down while in Highlander mode. To combat this, we sacrifice a Flash for Cleanse, which is a much better spell now that it removes the ignite debuff. Cleanse coupled with a Highlander will make Yi virtually inescapable and non catch-able. Ignite is our second summoner spell and is used mostly to finish off low hp enemies that are retreating or to debuff a champion that relies on spell vamp/ life steal. You can replace Ignite with Flash or Ghost if you'd rather be really OP and unreachable but I like ignite for the early damage and healing debuff.

AP Master Yi has a unique roll in team fights and can get really fed really quick if played correctly. In team fights you must never be the one to initiate a fight. Let me repeat that, DO NOT initiate! Let your tankier teammates take care of that. AP Master Yi's job is to take out the enemy carrys when they are over-extended or have low HP. Stay back and let your tank and/or melee bruiser soak up damage and go in for the kill or even to do AOE damage with your Alpha Strike. If you find yourself taking a lot of damage after you Alpha Strike into the battle, calmly press W and watch as your health instantly replenishes and the enemy cannot damage you because of your bonus 300 MR and armor at lvl 5 Meditate. If the enemy uses CC or some ability that disrupts your heal (especially an ignite debuff), make sure to either use Cleanse or the active on Zhonya's Hourglass. Do this, and pray your teammates are competent enough to keep killing the enemy team while they focus you.

If you survive the onslaught of enemy damage, your alpha strike should be off of cooldown by now. Use it to avoid taking further damage and finish the enemy team off with the damage it does. Make sure to use Highlander when going for a kill. Let me repeat that, make sure to use Highlander before killing an enemy! Your cooldowns instantly reset when you get a kill during highlander and it's essential if you want to continue to chain kills and do a lot more damage. Highlander is what makes AP Yi viable. Without it, he's not even worth the IP to buy him.

Thank you for taking the time to read my guide! As my first guide, I hope it was a pleasure to read and I hope it flowed well in it's grammar. Please let me know what you think in the comments! Criticism is my friend as it will help me make better guides in the future! Also, be sure to comment how well or (hopefully not) how bad you did using this Guide/Build. Remember to vote/rate as well! Peace out Summoners!