Its a fun ap-as teemo build; you start off with good mana regen and atk speed (for laying shrooms and harassing with blinding dart) using Nashors Tooth . Maxing out blinding dart is awesome since it does a fair bit of ap damage plus can blind for about 2 seconds! Getting rylais gives teemo some much-needed health and not only makes his shrooms uber strong, but gives them even more slow! The rest (if the game lasts that long) is upto you (more atk speed! or more defense as needed).
SHROOOOOOOMMMMMMMM THE **** OUTTA THEIR JUNGLE! AND GL HF!
P.DiddyXD