Master Yi Build Guide by wakkydude
Not Updated For Current Season
This guide is about building Yi for ridiculously quick kills late game. While early on he has a few problems settling in by the end of the game he can be unstoppable. It's a nooby build but a rewarding one.
Start out with the Doran's Shield and Berserker's Greaves. These should get you up to speed and give you a bit of opening power. As soon as possible, buy a Chalice as early as you can as you will have issues with mana if using your abilities effectively.
From there, get to work on Trinity Force. I choose to build it with the Zeal and Phage but it is not mandatory if you spend little time at base. Once you have Trinity, your biggest priority is stacking kill after kill with your Highlander and destroying teamfights. When you can, buy Zeals and then Phantom Dancers. If you want, ditch one of the Zeals for another Trinity Force, but this is only usually reserved for when the game lasts +45 minutes and you need an even harder push.
By now, your attack speed will be ludicrously high and with a combo of Highlander and Alpha Strike you can get in and out of teamfights with ease and kill less tanky characters almost instantly. Watch out for CC as it will very quickly destroy you as speed is the priority. It's a nooblord build but a pretty effective one at times.