Teemo!!!!!!!!!!!!!!!

       TEEMO THE SWIFT SCOUT.(Noiree,2013,p.1)

Teemo is a legend among his yordle brothers and sisters in Bandle City. As far as yordles are concerned, there is something just slightly off about him. While Teemo enjoys the companionship of other yordles, he also insists on frequent solo missions in the ongoing defense of Bandle City. Despite his genuinely warm personality, something switches off inside Teemo's mind during combat so that the lives he must end while on patrol do not burden him. Even as a young recruit, the drill instructors and other trainees found it a little disconcerting that, while Teemo was normally charming and kind, he turned deadly serious and highly efficient the minute combat exercises began. Teemo's superiors quickly steered him toward the Scouts of the Mothership, which is one of Bandle City's most distinguished Special Forces unit alongside the Megling Commandos.

Skills

Priority sequence:
 Noxious Trap -  Toxic Shot -  Move Quick -  Blinding Dart

Camouflage
If Teemo stands still and takes no actions for 2 seconds, he becomes stealthed indefinitely. After leaving stealth, Teemo gains the Element of Surprise, increasing his attack speed by 40% for 2 seconds.

I think this passive is fantastic! Use it to rush to your lane at the start of the game and become a living ward, providing sight for your teammates in the bushes, or for a sneak attack. Remember the 40% increase attack speed for 2 seconds! (Note: to prevent your auto attacks from hitting anything in range, press 'S' where you want to Stop.)

Blinding Dart
Obscures an enemy's vision with a powerful venom, dealing damage to the target unit and causing all attacks to miss for the duration. Deals 80/125/170/215/260 (+0.8 AP) magic damage and causes the target to miss all of their attacks for 1.5/1.75/2/2.25/2.5 seconds.

I put an early level 2 point into this skill. It extends the range of our harass, does decent damage and blinds - which is great against any melee who chase you or for preventing gold farm in your lane. I find that one point is enough and our other skills are much more important to max first.

Move Quick
Passive: Teemo's Movement Speed is increased by 10/14/18/22/26% unless he has been damaged by an enemy champion or turret in the last 5 seconds. Active: Teemo sprints, gaining twice his normal bonus for 3 seconds. This bonus is not lost when struck.

Fourth point goes in here and max it third. I place higher priority on this than dart because of the amazing movement speed boost. Plus it's Active will allow you to escape almost any gank.

Toxic Shot
Teemo's basic attacks poison their target, dealing 10/20/30/40/50 (+0.3 AP) magical damage upon impact and 6/12/18/24/30 (+0.10 AP) magical damage each second for 4 seconds.

First point here and this skill should be maxed first after our mushrooms. The majority of our damage will come from this skill. Remember that the DoT does not stack, but it is refreshed upon auto attack. This skill also let's us run away from a fight and still end up killing the enemy with the DoT. With the recent buff to this skill, attack speed is now even more important. Our on-hit damage with a +30% AP ratio is pretty good, taking chunks of life away like a boss. I like to put our first point here because it makes getting last hits extremely easy.

Noxious Trap
Uses a stored mushroom to place a trap that detonates if an enemy steps on it, spreading poison to nearby enemies that slows movement speed by 30/40/50% and deals 200/325/450 (+0.8 AP)magic damage over 4 seconds. Traps last 10 minutes, Teemo can store a maximum of 3 traps on his at once.

Being our ultimate, you should put a point in here whenever it become available. As an AP Teemo, these mushrooms hurt. They hurt A LOT. I can't even count how many kills I've received while back at my base - make sure place them in high traffic areas where minions are not likely to burst them. I'll cover placement more in depth in another chapter.
(noiree,April 12, 2013,Teemo - AP Yordle of DOOM [S3 Updated!])
http://www.mobafire.com/league-of-legends/build/teemo-ap-yordle-of-doom-s3-updated-209977