This is what counter mres and counter-picks are for. You can easily stun her and she stops her ult.

I really hate how people complain about Katarina. Her base stats and ap/ad ratios are terrible and she's extremely easy to counter.

"Even with counters and stun, she still does a lot of damage."

I have a question; how? If you cc her right when her ult starts, you essentially have taken away half her damage. You also can't forget the fact that she's an assassin. She's MEANT to be able to burst away your entire health bar if you don't build properly, make a mistake, or simply get counterpicked. If you remove her burst, what does she become? Don't forget that she's already been hit by a nerf and she's getting hit by another that screws over her laning phase.

But assassins are meant to take out a single target instantly.
She deals AOE damage and can move on to burst down another target after killing (or getting an assist on) the first.

But here's my opinion(and feel free to disagree with it).

Yes, I agree that she does have the ability to take down multiple champs like dominoes, but she's completely reliant on her passive. Here's the thing. If you can save one hard CC and use it on Kat, you've essentially turned it into a 4v5. She'll die immediately due to the fact that she's extremely squishy and if she doesn't die, chances are she'll be unable to chain her kills due to her low hp. You've essentially negated her presence in the team fight.

hue

learn to counter her fuucking noob

You stop a snowball at the top of the hill, not the bottom.

No but seriously now, it's enough.

I don't get why so many people believe Kat is some ultra uber Goddess of untouchable-ness. CC, dismantles, her. You can have a full string all set up, the enemy team is ripe for a nice Penta off your Ult; You Shunpo into the fray. Time slows down, in your mind you can hear the glorious announcer sfx of "PENTAKILL - ACE'd" and yet... for some reason, it doesn't play :O

Something has gone horrible wrong in the wondrous land of Noxus, what has halted our Apex Predator of Steel and Style? What could have possibly brought about this delay in her magnanimous glory?!

Oh right, ANY Crowd Control skill in the GAME.

Oh noes.

Noxus falls silent, a hush over the wonderful land. The cheering dies down, children begin to cry and throw miniature foam daggers onto the field. The only sound heard upon the Fields of Justice is;

"You have been slain."

If they nerf her any further than they already did, they might as well remove her from the game.