Passive: Double Strike
Nothing fancy here really, just some extra damage. If you have this ready to proc when you're about to gank you can pull off some nice burst, especially when you activate
Q: Alpha Strike
A great ability for clearing the jungle in record speed, although it does rely on chance. This ability also works great as a gap closer and even an escape tool. For AP Yi, this is your bread and butter.
You always end up on the person you originally cast the spell on, unless that target died before the animation ended, in which case you will stay in the original location. (Also, when this happens it glitches and the spell doesn't visibly go on cooldown, but the cooldown is still there)
The animation of this spell is slightly delayed. Be cautious about casting on foes that are running towards brushes because you might get baited hard. Also, it's hard to get this spell off on foes that are about to enter brush. So if you're chasing someone don't waste valuable time casting a spell that will just stop once they enter the brush/fog.
Although the cast range is only 600, the AOE radius of the multiple targets hit extends its range even farther. For example, is that champion getting away with low HP and you're just out of range? Then try hitting nearby enemies (minions) and there's a chance they'll get hit, too!
Use it as an escape! Simply use it on a minion that's in the direction you want to escape you'll put some nice distance between you and your opponents. Just tower dive someone and your
got refreshed by
? Then use
again on a nearby enemy minion to help secure your escape.
Okay this one is harder to pull off and requires precise timing, however, once you do the enemy will shit their pants. Here's how it goes: you're chasing an enemy and you know they're about to Flash over a wall. As soon as they get close to the wall they're going to Flash, this is when you use the delayed timing of Alpha Strike to your advantage. If you cast it just before they get to the wall then by the time they Flash over your animation will be going off and you'll catch them on the other side! Note, this might also backfire if they're Flashing into dangerous territory, such as their base or a tower, user discretion is advised.
Another difficult trick to pull off. It requires immense anticipation of enemy skills and a great deal of luck. This is how it works: during the animation of your Alpha Strike you become untargetable, similar to Vladimir's pool and Shaco's ulimate. So, you can use this in many ways to avoid enemy spells. Is that Ashe or Ezreal ultimate headed straight for you? Assuming you can't juke it (for whatever reason) try casting your Alpha Strike on nearby enemies and watch it zip right through you! Now that requires a ton of lucky mostly, but you can use it in other ways that requires more active skill. For example, you can anticipate someone's stun or [skill shot] snare and potentially evade it by becoming untargetable.
As AD, this is a rarely used spell, but it has a few nifty quirks. Is that Karthus ulting and you don't want to die or take unnecessary damage? Then start channeling this for a huge buff to your resistances. Are you fleeing the battle but have an annoying DoT ticking on you? Then use this to heal through its damage! (Doesn't work so well through Ignite, but it's worth a shot). Starting to get focused in the team fight? Then cast this (when their CC is on cooldown preferably) and you'll laugh at their futile attempts to finish you off.
As for AP, this spell is miraculous. Its maximum heal has a 400% AP ratio, which is the highest AP ratio of any spell in the game! If they have exhausted their CC (and they don't apply Grievous Wounds to you) then you can pretty much heal through any amount of damage.
E: Wuju Style
A very basic ability, it simply increases your damage. Yet there are key moments when you want activate it (and when not to). First off, for AD you want to make sure you activate it right as you're about to start attacking during fights to maximize damage. Secondly, you can use it right as you charge up your
to maximize your damage during the jungle and pushes. Lastly, and more importantly, don't use this too early during the jungle camps. Once the active dissipates so does the passive. This results in a loss of damage (you don't want that). Also, you don't want to cast it too late either because it won't be off cool down by the time you reach the next camp.
For AP Yi, once you acquire
you can use this spell cast to proc Spellblade. So, you don't want to activate it right as you ult as you would with AD Yi. Rather, you want to cast your
, wait 2 seconds, and then activate this ability to maximize your damage.
AD: When you reset your cooldowns from
it gives you the passive from this skill again. Thus, you actually retain the active and passive damage. However, as always, don't recast this ability until the duration expires or you will lose out on damage because it will remove the passive again.
A tremendously powerful ultimate, but poor timing can negate its usefulness. If you use it too soon (mainly during Rank 1) you won't have it up to maximize your damage and you won't reset your cool downs either (which is extremely detrimental in a team fight). Also, if you know you're about to get hit with a stun then don't cast it. Every second counts with this ultimate and you don't want to be stunned in place with it activated. Once their stuns are blown then activate this to watch their entire team tremble in fear!
You can use this to push buildings very effectively. As AD, with this and
activated you can steal buildings faster than any other champion in the game.
Don't forget about the slow immunity and speed boost! Use this to leave your enemies in the dust and laugh as they blow all their slows on you. Most importantly, you have to make fast car noises when you use this ultimate to maximize its effectiveness.
The cooldown resetting component of this ability is marvelous. It is what enables Master Yi to have more Penta kills than most other champions in the game (Katarina is his rival in this regard). Hopefully, you'll manage to land a killing blow while this is activated and you can spam all your moves again. Most importantly, you can spam
to bring about disarray to the enemy team (whether it's killing everyone or simply making your self untargetable to buy you a couple precious seconds). Keep in mind to not reactivated your
until they're about to expire. That way, you can maximize the duration of your spells to reach the full potential of your damage.