this is my first build, sorry if it is not the best, this is my build i made and used for twitch for a while, im gonna keep this breif cus of it being my first build

the 22/0/8 skill i went with was so i had a good couple of boosts in offense a good getaway move that got improved and i got something that'll get you a small bit ahead of the game with your leveling which will show as useful for ganking

i chose to get 4 to 5 speed and crit chance runes for my seals and marks and for my glyph getting ability power and spell penetration, reasons, AP and spell penetration can boost your expunge quite nicely its also a nice little smack if you have malady stack on them, attack speed i have in here for the simple reason, more speed more stacks, more stacks more damage, and crit chance is here for the obvious reason, to crit more

Twitch is a fast hitting ranged champion as you all know, in my opinion he has the most balanced poison with a pretty nice couple of nukes for it including Expunge and Spray and Prey, and using them to their fullest and using their range to your advantage

Pros
fast hitting
poison
nuke that can be stronger with the poison stacks

Cons
squishy
one of the champions the enemy will focus on to keep down
oracle can really screw you open

In my skilling tree i ended up skilling so you max out your main damage doer first,expunge getting ambush first getting expunge next and getting the slow, debilitate, early at level 3 the rest is focusing on expunge and ambush until they're maxed out then your set

alright the above is the very basic way to put all of the purchase order, heres the real purchase order
Dagger->Berserker greaves
if your doing good in the beginning
Black cleaver->Malady->Sword of Divine->Phantom Dancer
if the beginning of the game is going slow or your not doing very good
malady->sword of the divine->black cleaver->phantom dancer
so in conclusion either way your getting the same things just gotta be smart as the match is going but some major highlights would be Black cleaver with the stacking of an armor reduction (3 stack) malady having a magic resist shear (4 stack) and sword of the divine that after every 4th attack you do 100 extra magic damage that makes this all a very deadly combination
and if you ever have the feeling that black cleaver wont do enough for you get madreds bloodrazor because its got the little perk of hitting for 4% of the enemys max health in magic damage to add onto that fact

when your getting your spells set up you can chose a couple of things


Ignite, which is in your specs which while its on cooldown itll give you a bit of a boost to your ability power

Ghost, for those getaways that will take a while or when trying to get away fast to get back into ambush

Flash, its a nice thing when your trying to gank and get away

Finally, If you see a need for it, Clarity because at some points you'll be so close to a kill but not have enough mana to pull it off with your expunge or to get someone to slow down while trying to get away

if you do all the build here correctly you can get the dragon down (3v3) easily after getting black cleaver or malady and in the fight against baron you can 2 man it with someone who can tank easily and if your going to a lane with a load of enemy minions dont be shy to use your spray and prey ability to get your poison on all of them then nuke them so they can give you loads of money

I hope you liked my twitch build, again this is my first build, please comment or give me some suggestions to make this build better