Hi there guys.I have to tell you this is my first build so I hope I realized it good and I will try to upgrade it often.In this build i will show you the dominating part of Twitch,The Plague Rat.I am sorry if u can not understand some of my words because my English is not the greatest.

With these runes u can get a good advantage in early game with the flat damage runes and the crit chance runes will help you reach a big crit chance from low lvl.

My masteries are typical for a AD champion so you can adjust if you think they are not helping you enough.

The items I choosed are giving you the maximum attack speed with Yommuu's Ghostblade.With your high crit chance and the AD u have you will deal high amounts of damage,beeing able to deal multiple kills with your ultimate.
If your enemy team has tanks try taking Madred's Bloodrazor instead of Bloodthirster and if you have problems with your life try taking Frozen Mallet,replacing your Yomuu's Ghostblade.
If u ask why I take Berserker's Greaves and not Boots of Mobility it's because I prefer more attack speed than movement speed but take take Boots of Mobility if you want to move faster.

I chosed Flash because it is a good escaping and chasing spell and Exhaust will give u an advantage in 1v1 battles and slowing enemies to not escape.
Instead of Exhaust youu can chose Ignite because it works well with your passive or Teleport if you want to gank often.I sugest teleport for Pro Players because the ganking sounds like that:you and your teammates place wards,activate ambush and fust before you get invisible teleport to the ward.This may also help youo kill enemies who are escaping a battle.
I don't sugest u to take other spells than the four I told you.

Pros:
1.with full build you can solo the baron
2.after you take Executioner's Calling u can start doing some jungle
3.try ganking often
4.in a lane,first shoot enemies with low dodge chance with your ulti
5.always be carefull at not entering in 1v1 fights with champions who are more powerfull than you
6.wait for a teammate to attack first in a gank
Cons:
1.only stay on your lane without ganking
2.never enter in the jungle for some jungling
3.first attack jax or champions with high dodge chance in team fights with ulti
4.not looking when ambush expires

Stay on the lane until you get Executioner's Calling then start killing some creeps in the jungle tryng to get the red buff for slow and damage and blue buff for cooldown reduction.You can also solo the dragon and the baron in late game.

Gank often as you can and let your teammates initiate the fights.

This is the perfect laning,ganking and kiilling build for Twitch.

CREDITS TO:Sill3nt killer and my friends Razvii,Orhorien and Yorazvy.