Teemo is in my honest opinion one of the greatest champions in the League. He can be build AD/AP or DPS or even made into a hybrid. This build mainly foucuses on Ability Power, however for teemo's lack of survival skills (even though he is a scout, go fuiguer) I have thrown in a few items to help deal with his "squishyness"

Pros: Stealth
Damage over Time, his poison will make those Shaco's that decive away with low health drop dead anyways.
MUSHROOMS, controll the map, and make the enimy Warwick be afraid to enter your jungle turf, also the mushrooms serve as mini sight wards.
Hard to catch (if your playing him right)
Easy champion you assist your team with.

Cons: VERY SQUISHY, Once Teemo feeds, its all over.
He has to stand still to activate his stealth.
Primary target in team fights.
Mushrooms become useless if enemy team has oriacle elixer.

Runes are pretty strait forward, I chose Magic resist glyphs because mages arent as treatening as tanks are to Teemo, so using my items for armor and runes for magic resist gives Teemo more wiggle room to have one more fighting item inteads of getting a magic resist item.

21/0/9 are the masteries taking improoved Ignite and Exhaust, however Exhaust can be swapped with Flash. Never swap out Ignite, it syncronizes well with your poison and the added AP you get from using it gives you a slight boost early game. Since your Blinding Dart blinds the enemy you can swap Exaust for Flash, I use both regulary so its up to your prefference.

Grab a Dorans blade, the 100 health will help you stay alive as well as boost the damage of your Blinding Dart. Some Teemo's grab an Amplifiying Tome to start, well I don't agree with that choice because: 1) your less durable and 100 health can be the differnce of geting to saftey behind your tower and 2) Amplifying Tome doesn't help your damage output with Blinding Dart.

After First Blood and laning till lvl 4 or 5 recall to home base and purchase Amplifying Tome and Boots of Speed, lane as long as you can perferably till you have enough money to grab Sorcerer Shoes and a Hextech Revolver but if you need to, grab the Sorcerer Shoes then come back for the Hextech Revolver. You will need the magic pennatration from the shoes to boost your poion so it is your priority for now.

After you have your Hextech Revolver finish the Hextech Gunblade, "Why the Gunblade Teemo?" is a comment I frequently get from my teammates, the answer is simple: AP, AD, Spell Vamp, Lifesteal AND a unique ative that deals extra 300 magic damage that also SLOWS the target that you can use EVERY 60 seconds! This item is nessasary for Teemo because you will be controlling top jungle (I will get to that in a minute) and the lifesteal will help you take out those neutral monsters while keeping your health up incase an enemy Warwick stumbles upon you stealing his beloved green\wolf buff.

Rylia's Crystal Septer, also nessasary for Teemo, Rylia's sycnronizes so well with Teemo's mushrooms, if enemy champ is getting away they spring your mushroom trap poisoning AND slowing them giving you enough time to finish them off or slowing their advance.

Now it should be moving into mid game, sell your Doran's Blade to get enough money for your next item. Depending on wether you are losing or winning you should choose your next item carfully; If winning-Rabadon's Deathcap because you should have the money to spend to get it, OR if losing-Nashor's Tooth because you will need the cool down reduction to spam your abilites to defend your towers and home base
After Rabadon's Deathcap grab the Nashor's Tooth or if you picked the Nahor's Tooth grab Rabadon's Deathcap

Your final item should generally be the Void Staff because of the extra Magic Penatration. With this item build your shooms will be bringing cries of "OP NOOB" from your enemies as well as scaring them from attempting to jungle.

Your final item may also be Madreds Bloodrazor or a Starks Ferver; Madreds if you are still losing and the enemy team has a fed tank (Cho-gath for example) or Starks if your enemy didn't decide to invest thier money in Magic Resist items (which would be really dumb on their part)

95% of the time you should ALLWAYS be top lane. Teemo does very well against other carries so you should be fine, however if you EVER see a Xin Zao, Garen or Olaf in top lane switch with somone else on bottom lane because you will most defenatly end up feeding like and like I stated earlier "When Teemo feeds, its all over."

Mushroom Placement- At lvl 6 grab your shooms and begin to place them in gank prone areas so you will be alerted the moment the enemy comes for you (and trust me, they will). In the top jungle place your shrroms all along the main path (the one that is crecent shaped that goes past dragon) afterwards place your shooms in all the bushes\entrances to all the neutrall minion camps. This will put pressure on enemy junglers and help you and your team keep track of them. You should also place shooms around the Elder Lizzard in the lower jungle to help your team.

Jungling- allways try to grab the jungle buffs before the enemy does, usually when your minions are puhing an enemy tower you will be safe to quickly jungle and steal their buffs and ward the jungle with your shrooms. I usually leave the Elder Lizzard buff for my team on bottom lane to have but if they indicate they dont need it or your enemy team keeps getting it I generally start paying Elder Lizzard more vists.

Working with your team- NEVER be the first ine to jump into a team fight, JUST NO! Your squishy and an easy target, you will be dead in under 5 seconds garanteed. Allways try to stay behind your teamates, you should never be caught out in the open. Talk to your team, if your going to gank they need to know so they can charge\retreat to your needs in order to get the kill. Kill Stealing is very easy with Teemo, it causes a TON of team hatred towards you so be aware and dont rush in to kill if your teammate clearly has the advanatge and the kill. "Be kind, and and just Blind" is my rule when it comes to avoiding Kill Steals with Teemo.

In the circumstance your team is losing begin placing your shrrom all over your home base, make it so the enimy cannot take 2 steps without getting a slowing-poison cloud to the face should he dare to try to take your nexus. I cant even begin to say how many games have turned completly from a total loss to a easy win just by staying cool and protectng your base with a mass of shrooms.

With this build I never have any problems on a 3v3 map, infact most of my games are won before I can finish my Rabadon's Deathcap. 85% of my games with Teemo are assuredly victories and I recive many complements on my unique playstyle.

Note: this build does NOT work on 5v5's because you do NOT have enough armor and magic resist to survive in team fights on a 5v5; so PLEASE do not try this on a 5v5 match and blame me for your most certian failure.

Remember: just have fun, playing Teemo is all about that. You will be foucused down my enemies often and you cant let the pressure get to you and cause you to lose your cool with your teammates.

P.S. Don't forget: when the enemy team screams and hollers "OP NOOOOOOOB" just say "Teemo loves you when your angry" garanteed to make them either rage quit or stop harrasing you :3

Please Comment and Rate, (1st guide I've ever done) Thank You for reading my guide; hope it helps you on the fields of justice.
~Silentknight121~