I see a lot of people who don't understand Twitch wondering why he is so nerfed. It took me a lot of games to understand Twitch's role and how to win with Twitch.
First Twitch's skills. The fact that Twitch only gets bonus attack speed after being stealthed means that he doesn't farm or defend a lane well. Twitch is a roamer, assasin, sometimes duo jungler, and sometimes lane holder to soak xp/gold while someone else is B. Twitch is not a laner. This means you need 3 solos.
As a roamer, Twitch has the capacity to commonly decide games within the first three levels. Twitch accomplishes this by repeatedly zoning and killing both the opposing teams solo lanes from gold and xp, and killing the opposing jungler if possible. This gives your team a large enough advantage that when team fights roll around your team can win even with Twitch dying in seconds after unstealthing.
Remember, as long as your team is obtaining gold and xp from all three lanes and the forest, and the opposing team is not, you should win.
Start with stealth, Doran's blade, and 21/8/1, and 38% attack speed from runes (full set). Exhaust/Ignite.
At level 1, show up behind one of their solo carries and unload. Exhaust and ignite if you can get a kill.Their solo now has to go back to heal, and arrives back to face your level 3 teammate and is subsequently destroyed.
Repeat with other solo lane. Stick around for a kill if they don't go B. The goal is to remove lanes of gold/xp from your opponents.
Skill Stealth > Expunge > Stealth
Soak xp from the solo lanes, and continue to xp and gold zone your opposing solos. Pick up some boots and a few health potions as well. Counter jungle as well if the oppurtunity presents itself.
You need to accomplish this before their jungler clears the jungle (level 4) and can gank/interfere. This makes your solos gank-proof due to a level advantage, and makes the opposing solos vulnerable to ganks due to a level disadvantage.
Around levels 4-5 you will notice you are falling behind on xp as well. Now go duo jungle and duo gank with the bottom solo who was 2v1 and should be a really tough bruiser with ult to hide behind. Lane behind the bottom bruiser until mid game.
In my experience, Spray n Pray is actually pretty irrelevant, and is actually bad to skill up. Because spray and pray shots can be dodged by movement, you don't want to actually skill it up until after teamfights start. Unless you are team fighting, it generally reduces the damage you deal.
The game should be well decided before you ever put a point into Spray n Pray, which makes all the nerfs to the skill pretty irrelevant.
Since you are roaming, some gold/5 items are nice.
A decent build is Dorans, basic boots, Philo Stone, Ninja Tabi, Heart of gold, Black Cleaver, FM with some health pots sprinkled in.
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Chingmeister ?? Senior Member