My builds are created after a long playing a particular character. I mastered it and play a ranked game. If i will win, learning, play another champion. This situation requires a perfect build, in my opinion, this is like that.

Runes armor penetration and attack speed are helpful in obtaining the first attack to kill the increasing damage and attack speed. Also useful in the later stage of the game as opponents buy armor.

All Items in this build godlike form. Master yi has a high attack damage, high chance of critical strike, enough HP, high speed, both when attacking and running. Build is a little expensive(14 470g), but thanks to him we are feed all the time and we have enough money to finish it with no so long game and you don't need a full build to be unstoppable.

At 1 lvl we have to be carefull and be passive, at 2 lvl when we have first skill and third we can get kill with litlle help of teammate(We have enough attack speed, with first skill we can catch an enemy and with third skill we are increasing our attack damage and need ony 3-4 hits to kill him).At later game(after 6vl up) we can gets multikills alltime(passive of ulti renews our colldowns and we can again use first skill to catch next enemy and to use ulti and kill all of enemy so easy and so fast). You can go alone only when you have active ultimate skill, cause thanks for him enemies cant stun, slows and fears you and you have easy road to run. Ghost can be helpfull then. With attack w8 for your team mates, never attack alone. You cant get focus on you. Good luck and have fun.