Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
ArP Teemo, On Duty!
First Start the game off by purchasing Vampiric Scepter
On your first break to shop, get Mercury Treads
Then on your next break get Phage
Then Giants Belt
Finish Frozen Mallet
Then get Recurve Bow
Finish Last Whisper
Get Cloak of Agility / B.F. Sword in thew order that you can afford
Finish Infinity Edge
Finish The Bloodthirster
Finish Guardian Angel
Im not going to go into the specifics of Teemo playstyle, although i will stress that you need to abuse your ability to kite, since you aquired Frozen Mallet very early. You need to have mushroom scouting, as usual. Basically if you are going to get ganked, you will know in advance with proper mushroom scouting, and usually you can do something about it. Finally, do not think you are a tank just because you have Frozen Mallet, you need to stay in the back, or try to flank for team fights, initially blinding enemy AD, and sniping the other sides DPS.
I have been quite successful with this build, and currently have 100% win ratio in rated 5v5 solo with Teemo. Although i havent played to many games =P with a overall K/D of 43/12. Please do not hesitate to try this build just because frozen mallet is rushed, and the initial thought process usually ends in people thinking "no damage?!?!". In the end your kiting ability makes up for the lack of damage until you begin to build the damage items. After you get Infinity Edge, your critting 800's with 60% ArP. Thanks for reading this build, and comment if you feel something should be changed. (Sorry for the lack of detail on my first build xD)