[{quoted}](name=A Miss Fortune,realm=NA,application-id=3ErqAdtq,discussion-id=f7H9b8om,comment-id=0004,timestamp=2015-09-15T22:15:32.177+0000)
Teemo needs a rework. He'll never be viable in his current state because if he was, he would just prove he's the most toxic champion in the game. He's extremely weak right now but It's because he's so unfun to play against. Riot most likely has always wanted to rework him, but due to his supermassive fan base it will most likely never happen since his shrooms, blind, and poison would probably be removed or changed a ton.
Now I won't be the one to say what's fun and not, but typically his shrooms, point-and-click blind, and poison have all combined together to make Teemo extremely toxic, yet they're also the identity of the champion. Reworking him would completely change his identity if the rework would to be successful and that would just enrage his fanbase. I respect Riot a lot for not ruining his identity and allowing his fans to enjoy the champion, but still his kit is way too unfun.
Nothing in Teemo's kit was overpowered. In gold+ it's almost impossible to keep good shroom coverage down because massively-tanky supports just walk through them and take no dmg until you have 4+ items completed (ie 35+ minutes). If you upgrade a sweeper you can clear large areas quickly. Teemo's kit could be countered by items or decision-making or teamwork, which is what Riot has been trying to add to many champions for a long time.
You could lane-counter pick him. You could have a jungler camp him easily pre-6. You can counter him with item choices. He might have been one of the best balanced champions in the game.