Nerf god damn katarina already. She is clearly broken
http://champion.gg/champion/Katarina
Numbers don't lie.
She excels in any elo. You can say she has counterplay, which is CC, but CC counters freaking everyone. Its just extra important to CC katarina, because she is broken.
When i'm in a teamfight, i'm not thinking 'katarina, katarina, katarina' there are 4 other champions I need to worry about as well.
What is the only thing katarina doesn't excel in? Deaths. Oh but don't worry, she's high risk. Because if she fails to pentakill your team she might not be able to make it out.