Welcome to my first build guide. I decided to try my hand at writing this guide because I'm really surprised someone hasn't already done one. I really think with the new itemization in S3, Teemo is very viable in just about any style you like to play. AP is powerful for the big hits and deadly shrooms, but can lose some value mid to late game in team fights. AS/AP Hybrid addresses the team fight aspect without sacrificing much in the big boom shroom department. And, this AD build sacrifices the boom of the shroom for better team fight/1v1 ability.

Keep in mind that I am, in no way, saying this is the best build out there for Teemo. It's just another viable option IMO.

Overall pro's and con's haven't changed for Teemo... So, what I'll do is pro/con vs. AP Teemo.

PRO'S

Higher sustainability...due primarily to life steal.
Better ranged AoE.
Easier to be effective in team fights and 1v1's.

CON'S

Slightly low burst.
Shrooms aren't nearly as deadly.
Less mana and mana regen.
Fairly expensive build.

Item build starts out with the standard Boots and 3x Health Potion. You could start with a Doran's Blade or two first, but for this build I try to start building the items I will use later ASAP as it's a bit on the pricy side.

First trip back, I buy the Long Sword so that Teemo starts hitting with a little pop before finishing off the Berserker's Grieves.

After the grieves, I work on the Blood Thirster and Runaan's Hurricane at the same time. The key here is to try and save up for that B.F. Sword as quick as possible. That is really the only expensive component item in this build and you won't see it again until building the Infinity Edge for the last item. I like to finish the BT first so that it starts building that AD and Life Steal ASAP.

Next comes the Frozen Mallet for some health and slows and a bit more AD so that Runaan's Hurricane is not only hitting a bit harder, it's also slowing 3 enemies with every auto attack! You are now a very effective asset in team fights with solid AoE damage and slowing the enemy team. This can help save teammates that are trying to get away or help secure double and triple kills.

If the game is long enough or you're fed enough, you next will want to build Zephyr. Great all around item with great synergy with this build. You get AS, tenacity, run speed, cool down reduction and AD! A viable option to Zephyr would be Phantom Dancer. You get the AS and run speed, but you lose the tenacity, cool down reduction and AD for some more crit and unit collision avoidance.

Finally comes the Infinity Edge. Great item for increased crit damage and a lot of AD. A very viable option is to go with another Blood Thirster instead. It's a bit more AD and some Life Steal for sustainability at the cost of some crit and crit damage.

I went with Greater Mark of Attack Damage and Greater Quintessence of Attack Damage. I think these both have great synergy with Runaan's Hurricane (the core item in this build).

For seals, I went with Greater Seals of Armor to give Teemo some solid early game survivability (Rofl at mentioning Teemo and survivability in the same sentence!). You could go with the Greater Seal of Scaling Armor for better armor late game, but I am of the opinion that if their AD get to you you late game, you're most likely toast anyway.

Almost the same idea behind the glyph decision. Except this time I went with scaling MR due to the fact that I'm typically not as worried about AP's early game.

For masteries, I went with a very typical AD build. You'll notice though that I did not take Deadliness and Weapon Expertise . While I believe 8% armor penetration is very nice, I don't think it's worth the 5 points it takes to get it, and the 12 AD at level 18 from Deadliness just seems a bit lack luster IMO.

For summoner's spells, I went with Flash and Clarity.

Flash I like for quick escapes and also for securing a kill on some of the more slippery get-away artists like Wukong or Graves.

I go with Clarity because this build is pretty low on mana and has no mana regen. Your shrooms won't be doing a ton of damage, but you'll still want to use them for the slows and the map awareness.

One very viable option to replace Clarity with would be Ignite for a possible early game gank or two. Another option could be Ghost for better mobility.

You'll want to train Toxic Shot first and max it out by level 9. At level 2, train Blinding Dart and max it out last. Remember you're AD for a change and Blinding Dart won't do a ton of damage, and is just as functional at level 1 as it is level 5.

At level 3, you'll want to train Move Quick and max it out by level 14.

And finally, train Noxious Trap at level 6 and every time it's available. It still does a decent amount of damage with no AP.

I think AD is again viable for Teemo. I'll add more to this when I get some time. I just want to get it posted for now and get some opinions about the build.

To do list:

Finish up the sections (Pros/Cons, Team Play, etc.)
Add some more and different style coding.

I doubt I'll be adding a shroom map as that's been done in about 300 other builds and if you need that info, it's available.