Nasus requires everything that i said above that does not needed on Yi: short cd ability to proc spellblade(Q), Ms speed buff( nasus has no innate ms buff), mana problem, the ability to stay alive long enough to proc multiple spellblade passive multiple times. On top of that, Nasus dmg scales well with AP, both E and R ( AP nasus is actually a legitimate build).

The cost as much as ,i would much prefer to go for the IE instead.
Without cdr( which is generally the case), Yi's Q has 14s cd, you'll need to strike 8 times, assuming an attack speed of 2.0 which would take 4s to do. Even when assuming the target is not death by then, it's easy to see that IE will overall do a lot more dmg.
Moreover, either (R and Q) or (R and E) will be used at the same time in the start of the fight, and will not go off cd to be triggered again during the fight, meaning 2 abilities will worth only 1 sheen proc during the whole fight.
Another factor to take in to consideration is the disminising return effect of stacking movement speed. There are soft ms cap at 415 and 490, which, if you go beyond those soft cap, the added ms will be multiplied by 0.8 and 0.5 respectively, meaning that the ms buff will be a lot less efficient.
also has several advantages over trinity force: much cheaper, which serves as a mid game power spike item, and it allows you to split pushing effectively because low cd the ms speed buff active does not require you to attack to proc. Therefore, when you need to escape and your ult is on cd ( or you don't want to use your ult), ghostblade is the answer.

It's true that the mana and the ap are useless. But that doesn't make the item cost inefficient, it's like saying it's inefficient on nasus for example. Yi does have short cd abilities, Its Q is constantly getting refreshed by auto attacks so you can proc passive every time your Q is up, plus it procs when you activate your ult, when you activate your E, and when u do any aa reset with the meditate. About this item being expensive, yes it's pretty expensive thats why you buy first either zeal or phage, which are pretty helpfull by themselves. The fact that the mov speed bonus procs when you dmg means you can stick to targets better, yi is already fast but with phage's passive you've got god's speed, most of the times enemies wont be able to run away even if they flash, about starting with your ult to dive, well I might be wrong but I believe you should always dive with your ult. Also, you're missing the atk speed, the hp and the crit you get from tri force, which added to all of the previous makes it a pretty solid item for master yi, and it'll give you some unexpected damage

I don't agree with the trinity force as a item.
Firstly, Yi can't really make full use of the mana and ability power stats. Making the item not cost efficient.
Secondly, Yi doesn't have short cd abilities that he can spam repeatedly to procs the spellblade passive.
Thirdly, This item is expensive, Yi seriously needs tanky stats after botrk, should teamfights happen, therefore, trinity force will be delayed to late game, where its won't really do as much anymore.
Also, the movement speed bonus procs only when you have done dmg, meaning that you'll have to start with your ult to dive in, which will waste a few seconds of your ult as well.

Excelente Guia ya podre salir de Bronce IV :D gracias +10 y fav

I shall try out this build!!!