Made my first Pentakill with this build a bit weak from the start, but after i finish my Jungle item Guinsoos Rage blade, Hextech gun blade and Nashors tooth Damn! he's unstoppable!! You got my vote mate this guide is awesome AP Yi Rocks!!

What are your thoughts on using blade of the rune king over wits end? great build btw I played it last match and noticed the difference

great build. i just made my first Penta on lol :D
http://matchhistory.eune.leagueoflegends.com/en/#match-details/EUN1/1342564118/219285736?tab=overview

Did you know Hextech Gunblade also heals from Master Yi's true damage?

I gotta say it is actually pretty effective! xD

I followed exactly your build (excepts for the runes i went as on red and magic resist on blue + cdr) and in my first game following it i ended up with a score of 27/2/6. Dealt the most dmg of my team and got a Pentakill. A good 1/3 of my total dmg was magic, it's EXPLOSIVE!

I enjoyed a lot, thanks v.much sir :)

OH MY GOOOOOOOOOOOOOOOOOOOOOOOD!
ITS VERY REALLY MUCH DAMAGE

good made all the items help me alot man i did not think ap yi is a thing

Tried this and I must say its lot of fun and its working really well too :D

Let me know if you find any mistakes or have suggestions! :D I'm always open to criticism and discussion!