TEEMO EVER USED IN PRO PLAY?

He was used by TSM as a troll pick to go to a Game 3 so that Doublelift can get his 1000 kill during the regular season.

However, has been played, and gotten Pentakills, in the non major regions (Turkish league for example). Has been picked accidentally because of how Korean language works in LCK when people tried to pick something like Trundle and instead end up with Teemo XD. Not once, but several times (like at least twice in Summer LCK 2016).

China's LPL or LSPL might have had an accidental Teemo pick.

Most occurred in about a 2 week span of time all these Teemo picks. Most were accidental, in the Major Regions. While the Wildcard Regions had it for what seemed to be intentional cheese pick.

Not without the match being a "troll" or highlight match no, not to my knowledge.

Yes

http://lol.gamepedia.com/Teemo_-_The_Swift_Scout/Match_History not a lot lol

He was, and after that they nerfed his shrooms into the ground because "too oppressive on the map"

Was a couple seasons ago

Teemo has a 100% winrate I here he was played in one ranked game ever.

He was played numerous times as a troll pick(in the case of TSM, Hauntzer and Regi both played teemo in official pro games in the past) or sometimes as a mi%%%%%(hovering teemo for luls then didn't have enough time to swop to the right champion)

TSM once played him because they said if they got enough likes on twitter they would play him as a troll pick

It was played in a TSM game last season

Early Season 4, C9 vs TSM, Hai picked him mid. They won pretty convincingly, too - TSM couldn't do anything against the absurd map control.

Just last season, actually.

As a fucking joke, because he's a fucking joke.

Recently? Not really, atleast not in a serious match. However, he has seen some(not much, but some) play in seasons long gone past...