Remember to use the EXPUNGE wen you have 6 stack from your passive to deal more damage
EXPUNGE is an magic damage spell

The Phantom dancer is to get the most attack speed. with the attack speed and the infinity edge will you crit attack most time and deal "Tons Of Damage" the zeke`s herald you get the life steal you need to get more hp from minons. the Rod Of Ages is to get more hp and mana that will make you sruvive longer becous you will be the champion with low hp at max. the abblity power form the rod of ages makes your EXPUNGE deal more damage.

Pros / Cons Of Twitch

Pro's
1) I personally find him to be really fun to play
2) Can scout almost unhindered early game or even late game if they don't buy oracles (which as stupid as it sounds has happened a number of times)
3) Has a great aoe slow
4) Fantastic ganker
5) An ult that can hit the entire enemy team as well as work in tandem with his other abilities

Con's
1) oracles and wards require you to change how you are playing your game
2) You're squishy as hell, forget that for even a moment and you're doomed to failure
3) Rather reliant on his spells until late game when he can dish out the damage with relative ease
4) Reliant on positioning the WHOLE game. If you don't have great positioning, you're gonna get rocked a lot.
5) You have to be steady (this goes out mostly to the new players). I throw this out there because I made this mistake a few times when I was just starting out. Being squishy, you MUST keep your distance in a team fight. Your hand has to be steady even during a cluster**** otherwise you'll mis-click and accidentally get too close. This leads to minimal damage and a dead rat.