This guide is incomplete but I will continue to work on it.

If you're looking for a traditional Yi guide, this guide isn't for you. I don't know how to play Yi as a jungler or an autoattack carry. AP is engraved into my brain. Before I start, I'm aware there are other great AP guides on Mobafire and I really wish I had known about them when I started developing my own rendition of a great AP Yi. My reason for writing this guide is not to compete with the already available ones but to, yet again, test my guide writing ability and express my slight disagreements with the other AP Yi guides.

Whether you're a long time Yi fan or a new player, I hope everybody can appreciate the power and fun of AP Yi once this guide is all said and done. Please leave a comment; both positive and negative feedback are much appreciated. If you've read this far, be sure to include the word 'banana' in your comment. I want to see how many people bear with me through the boring introduction.

Pros

• Fun as hell to play
• Great laning presence
• He can mid against most champions
• Great sustainability
• Can take down towers with relative ease post Lich Bane

Cons

• Squishy when Meditate is down
• Crowd Control effects other than Exhaust really screw him over. Basically everything cancels Meditate. Ignite is extremely annoying. If you've ever been ignited after ult'ing as Mundo, you'd know the feeling well.
• Some champions just dominate him. He can't be played like AD Yi. He's just not viable. Play him as an AP Carry/Assassin and you'll be fine.
• When your team begins to lose, they WILL blame you. It can't be avoided. They assume that because you're built AP, your team is losing. (It's never true, people just need someone to point a finger at and who better than the trendbreaker?)

I choose to play Yi as a harasser early game. With a 1:1 scale on Alpha Strike, a smart Yi can keep the pressure up without pushing a lane too much. The runes I choose to use on Yi may seem a bit strange but, of the runes I've tried, these are the most effective to building an annoying ******* of an AP Yi. As with items, I've experimented on these enough to get this down to a science.

First, you're going to want some good ol' flat Ability Power to effectively be a prick from the moment Yi is summoned to the Fields of Justice. The best rune type for the job would be Quintessences. That said, go ahead and put on your

Buy some Greater Quintessence of Ability Power

To further amplify your damage, magic penetration works wonders for the mark slots. One of the secrets to this build is to have a ridiculous amount of magic penetration. So much that, in fact, you can effectively counter not only the flat Magic Resist (around 30) found on any champion, but you can counter most carries that utilize scaling magic resist glyphs. Get some

Buy some Greater Mark of Magic Penetration

When you're spamming Alpha Strike, you'll find that Yi has a huge mana problem. I used to combat this issue with mana regeneration items early game but I've found that using scaling mana regeneration seals can help with mana problems once you reach about level 8.

Buy some Greater Seal of Scaling Mana Regeneration

Lastly and most importantly, we need our scaling Ability Power glyphs. Anybody who has an Ability Power rune page should already have these. Endgame, these alone provide you with about 28 additional Ability Power. With your Rabadon's Deathcap, these provide you with an additional 9 Ability Power, raising that total to 37. That's pretty beast when you consider it adds not only 37 damage to your Alpha Strike, but an additional 37 damage to your Lich Bane procs and an additional 55 hp healed over the 5 second duration of your Meditate.

Buy some Greater Glyph of Scaling Ability Power

If you have any rune suggestions other than the ones listed, drop me a comment. I've tested a bunch but, as I said, these are the ones I've found to be most effective. You may find otherwise.

Item choice is what makes this build special. I've put a lot of trial and error into developing this build, all with due explanation too.



Your first item, which you should ALWAYS get, is Doran's Ring.
This item is perfect for any Yi. As an auto-attacker, AD Yi is extremely weak until level 6 so Doran's Ring can be utilized by both AP and AD Yi for a stronger Alpha Strike. This should bring your level 1 AP to 32. This item also provides mana regen, an extremely important element to early game Yi.



Your second item, which you should ALWAYS get, is Sorcerer's Shoes.
These are extremely important as, aside from the obvious additional 70 movespeed, you now have a total of about 29 magic penetration. Most squishies have 30 Magic Resistance which means you're now capable of doing near true damage to them having only two items. Alpha Strike is one of the strongest non-ultimate abilities in the game, and yours now does near true damage to maybe 70% of champions.



Your third item, which you should get in 80% of games, is Haunting Guise.
I originally got this idea from an enemy Kog'Maw who went AP and absolutely DESTROYED with his ultis. Since then I have incorporated this item into the builds of most of the AP champions I play.

This item is a really fun item. Most champions, when all is said and done, will have a bit more magic resist even if they aren't trying to build specifically tanky. For example, a champion like Karthus or Annie might build an Abyssal Mask. They generally build these things for the cheap Ability Power and MR Reduction stats. However, it does come with 57 Magic Resist. Another instance would be Mercury's Treads. Most people build these for the Crowd Control Reduction but get a small MR bonus. If neither of those trends apply, many enemies can have scaling MR Glyphs. It might not seem like a big deal but when you lane solo top against a Vladimir with 53 MR, you notice it. I've dropped many F-bombs over that ****, not all of them even with Yi. Your Magic Penetration will be 48.5 after this buy which means in actuality, it's 49. That's a lot of MPen.

So you have the basics. You've been relying on the base damage of Alpha Strike and your ridiculous MPen to do your bidding. Now you need to abuse that crazy 1:1 AP Ratio on your Alpha Strike or your 1:1.5 ratio on your Meditate.



Your fourth item, which you should ALWAYS get, is Rabadon's Deathcap.
This bad boy is where you get your early to midgame damage from. Start with the Needlessly Large Rod portion of it. If you only have enough for Blasting Wand since your last buy, you're either on a team that isn't in good shape or you haven't been using that Alpha Strike enough. Blasting Wand is only acceptable first when your lane partner is a scrub that refuses to buy wards leaving YOU to buy them. Alternatively, it is absolutely NOT okay to be that wardless jerk just to make Needlessly Large Rod your next buy.



Your fifth item, which you should ALWAYS buy, is Lich Bane.
I used to be the bad AP Yi that didn't use one of these. After a defeat as AP Yi, a guy on the other team told me I was completely stupid for not utilizing this. After which, I began building it first, which was also a mistake. Through trial and error, I've determined that immediately after Rabadon's Deathcap is the best place for this. Any earlier and you would be better off with merely a Sheen. After Rabadon's, you have a total of about 300 AP (around 380 once you complete the Lich Bane), making this vastly superior to the double damage offered by a Sheen.

You now have the core build completed. This is where you need to make a decision. If your team is doing a good job utilizing you as an amazing harass, you can continue to build pure AP. Alternatively, you can use your last two item slots (after selling your Doran's Ring) to go hybrid. I'll explain the benefits of both. After your Lich Bane, the outcome of the game should be relatively obvious and, if it's not, that means you're simply fed and should continue on the pure AP route. Otherwise, choose wisely how you choose to top off your build.

Pure AP

When your team isn't ******ed and knows how to commit to a kill and when to push, this is for you.



Your fifth item should be Morello's Evil Tome.
Not only does this item provide excellent Ability Power for its cost, it provides Yi with two things Yi needs most at this point in most games: Cooldown Reduction and Mana Regeneration.



Your sixth item, whenever you face a team that has more magic resist than they should, should be Void Staff. It's cheap AP and will raise your MPen to 49|49% meaning you first negate 49% MR and then further negate another 49 MR.

Hybrid

To finish hybrid means to give your Highlander and your Wuju Style some use other than to merely run away and proc your Lich Bane respectively. For that we have such items as



For the adventurous Yis out there, Hextech Gunblade is an item that provides lifesteal, AD, and AP. All of which are powerful assets to Hybrid Yi.



A regular to AD Yi, Infinity Edge is a great damage item that also provides additional crit damage. When paired with Phantom Dancer to achieve a higher crit rate, your damage output is increased exponentially. Also, a pretty sweet side effect is that Lich Bane procs CAN crit. I've tested this with not only Yi, but with Gangplank (Potential AP Pirate guide in the future? Perhaps...)



Phantom Dancer is a great item to increase Yi's crit chance, attack speed, and movement speed. Damage isn't too big of a priority for Yi as Wuju Style provides a sizable bonus. This is an all-around great item for hybrid and AD Yi alike.

Alpha Strike

To an AD Yi, this is a decent creeping tool. Junglers make use of it a lot as it has a chance to proc an additional 400 damage to any non-champion units. To an AP Yi, this skill is near everything. You'll need to learn to harass with this skill very well.

This skill hits a maximum of four units. Unless the target unit dies to a source other than Master Yi once Alpha Strike has been cast, Yi will appear at the target's location after the strike. If the aforementioned happens and an outside source kills the target unit mid-cast, Yi returns to where he cast Alpha Strike from. Generally you don't have control over the second outcome but I say this so you're not surprised when it happens.

To effectively harass with Alpha Strike, it is far safer and more efficient to cast on the minions near a champion than the champion itself. There are a number of reasons for this. For one, if you cast Alpha Strike on a champion and then, mid-cast, the champion runs into range of their tower, you are brought into range of an enemy tower and WILL take a tower hit having just damaged an enemy champion. Secondly, some champions you just don't want to teleport to. Think about it. Does standing next to the enemy Blitzcrank really sound fun? Hell no it doesn't. The only exception to these rules is when you can land a killing strike.

When you use this skill on a champion and you have your Lich Bane, make sure to auto attack them once upon reappearing to inflict the proc on the target enemy. This increases your burst vastly.

Meditate

"Is he trolling? Yeah, he's trolling..." are amongst some of the things you might hear when you use this skill. It gives you a ridiculous amount of armor and some health back while channeling so don't move or it will cancel the channel. To an AD Yi, this is a decent sustaining tool and not much more than that. To AP Yi, this is one amazing skill. You can heal up mid-teamfight and be back into the action with full HP. It also gives you the ability to tank for small periods of times. I've had to tank inhibitor turrets with this skill at times so don't underestimate it. This skill also means that without displacement CC ( Fling or Pulverize), ignite, or stuns, it's not possible to tower dive you unless the enemy is an extremely fed Nasus. It's also great for getting champions like Akali to waste their bursts on you.

Wuju Style

A simple filler skill. It provides passive AD which can be sacrificed temporarily for double that amount. It gives many Yi the ability to backdoor very well when paired with Highlander. To AP Yi, it's the skill you waste to proc your Lich Bane. When you have the ability to hit 500 damage on a tower in one stroke, even a skill like Wuju Style has its use to you.

Highlander

The reason you bring Ghost is for this skill. Not only does it stack with Highlander, but Highlander makes you unslowable. This is a great skill for chasing an enemy or running away. To AD Yi, this is the skill you rely on to get kills and down towers. Highlander gives you an incredible Attack Speed bonus and has a cooldown refresh when a champion is killed by Yi while it's active. This can also be used to proc Lich Bane should the situation call for it.