Teemo and Karthas Perm Ban?

You're thinking of One-For-All. Teemo and Karthus are absolutely toxic in that mode.

I got to play teemo last time

well vs teemo get sweeper and you can walk throught his shrooms 8/10 seconds if you spam it so its not a big deal

Because there's crap like who will make you regret the Season 5 change to make pink wards visible to everyone Good luck catching me! Hello, you have .3 seconds to flash before I lock you down for about three days Literally. Infinite. CC. If even one snare hits you should just AFK. I'm still going to melt your face, only this time I can do it with ult too. Have fun chasing me and eating all of the damage our clones do! Full AP never hit so hard. I build AP and hit better than Nidalee with greater prediction too. You are either Slowed or Stunned, there is no middle ground here. I'm still just as powerful as I am in Ranked, which is to say, still Overpowered. Hi, I scale infinitely Oh, I do too!

And the occasional If I land one single Acid Bomb you are going back to base either running all the way to your Inner Turret and recalling or waiting on Respawn.