Hello, and welcome to the very condense AP Teemo guide by Scarydeep. Although Teemo hasn't seen much love in pro games, it is very possible to do very well with him if you play him right. He can be seen in top or mid with this build. I may add an optimal mushroom positioning chapter later as well other detail, so if something important isn't included, let me know!

Typical AP carry runes, CD reduction for those mushrooms that do so much of your damage.

Typical AP carry masteries. Movement speed in utility to combine with move quick/ghost and let you have more map control with your mushrooms, as well as chase.

Rushing Morello's will give you a good amount of CDR and some nice AP. Rabadon's for straight up damage, Rylai's for some survivability and slows on your mushrooms, void staff to counter MR, and finally Zhonya's to make sure if you get focussed you have a chance of living. Doran's rings could be helpful, but aren't necessary unless you are having trouble.

Start with Q then E to do some early game damage. Then get your W once just in case. Maxing E first lets you spam your enemy with dots that do high damage and give you a lot of lane presence. Then maxing your Q allows for high damage output and harass combined with your E. Maxing W last but getting it once early makes sure you can trade with your enemy lane, but get away if needed. Get your ultimate whenever it is an option, as it is one of your highest damage ability with a slow.

Getting ignite and ghost will make sure you can finish enemies off and catch them or run away. Ghost instead of flash allows synergy with his W.

Just so you know, mushrooms can explode from creeps, so position mushrooms carefully.