I pretty much just randomly came up with this build by improvising.

Since it's nearly 5am, I'll make this quick:

Doran's Ring > Warmogs > Boots of Swiftness/Berserker Greaves > Atma's impaler > Frozen Mallet > Infinity Edge > 2 Phantom Dancers

Masteries: 21/9/0

Why?
Dorans ring helps when laning a LOT. As long as you learn Meditate at level 3 or 4, you'll be fine.

Warmogs works very well with Yi, as he is a brilliant farmer, yet will be almost indestructible. Just to abuse that ton of HP you have, why not add insult to injury?
Atma's impaler will give your decent amount of attack damage - certainly enough what your current level.

Frozen mallet speaks for itself - Attack damage, a great unique passive and all that HP, which add perfectly to your stockpile of AD.

Now to bring in the pain - BRING IN THE INFINITY EDGE!! This speaks for itself!!
Just to finish things off, sell your Dorans ring and boots of swiftness/Berserker Greaves and add two Phantom Dancers! Since the Phantom dancer provides 15% speed of its own, you won't have to rely on those grubby boots any more.

Crit Chance without masteries/runes = 98% (Atma's - 18%, Infinity Edge - 20%, Phantom Dancers - 30% each)

Crit chances with 21/9/0, yet no runes would be 100%

I've never fully completed the build, due to the lack of time given (enemies surrendering), but I know it would be absolutely perfect.

Yi would have about 3600-4100HP (You'd get about 80AD from Atma's impaler)
Frozen Mallet adds a fair share of AD.
Infinity edge adds a LOT of AD
Phantom Dancers add on the DPS.

So guys, what do you reckon? I've only used my build twice, but it's been successful both times.
Another reason why this build is pretty effective, is that it enables Yi to tank turrets by himself, meaning he can be destroying enemy turrets while the enemies are at your Inhibitors. (I recommend Teleport and Ghost for this to work efficiently).
Here's a printscreen of both the games:

Attached Thumbnails

 

I think I remember a guy playing a game against my team with this build, I was a bit stunned when I saw warmogs on Yi, trouble was he couldn't get enough farm for damage/crit items and the last thing he got I believe was Atma's Impaler, but by then we had an enormous advantage.

Basically early-mid game he was a 3k HP behemoth that hit like a mosquito and rarely did any help in teamfights, we just ignored him. Later on he could dish out some damage but by then we were just overfed by winning every teamfight and regularly farming dragon/nashor.

looks like Dark Side of Yi, slightly modified i'd take mallet first, anyway, helps more with damage/slow.

Any mage worth a **** will burst you down like a snow cone cuz of lack of mr, and as they say, you got no dmg until late game : \

viability: Low.

I never built Master Yi that way... I'd start with a Meki Pendant (7 mana/5 sec) and 2 health potions.
Nashor's Tooth - Berserker's Greaves - Youmuu's Ghostblade - Infinity Edge - Phantom Dancer - Trinity Force
If the game continues too long, get a 2nd Trinity Force to replace your Nashor's Tooth.

It's not the best build at all, but it worked in our match pretty fine (I singled their nexus towers and their nexus and I destroyed their team in general).

As far as your build is concerned:
It's not a good idea to start with Warmog's or Atma's Impaler, it costs too much together.
It costs like 5000 gold, which is a Trinity force and berserker's greaves or a brutaliser-phantom dancer-berserker greaves etc etc...

I wouldn't build Master Yi tanky :-)

Warmogs atmas yi does surprisingly good damage even early game and is a ***** to kill. People will tower dive a 1/4 hp yi and then be like "wtf?!" when they fail to instakill you and die before checking to see the giants belt or warmogs in your inventory. The damage scales up as yi farms his warmogs and then you can either run a dps set up or keep going tanky (frozen mallet and a banshee's sounds good to me).

it works only if yi heavily Stats E early game

Bump