Kass's problem is in his Q; not his ult
I realize this is going to sound weird as hell because the first thing people think of when they think of Kassadin, they think of some purple freak materializing out of nowhere, one-shotting them, then materializing in the distance while making love to the wife of the now-deceased, but this problem mainly comes from his Q.
This is because of what his Q is. It isn't necessarily bad that his Q is a damaging point-and-click spell, but his Q is extremely problematic, both in lane and late-game because of the raw power.
Firstly, his Q is one of the best bullying tools. Kassadin's mana problems are pretty minor unless you suck at using his ult, so he's going to spam Q on you for the entire lane while trying to sustain it with W. This not only makes part of your damage to him useless, it also deals a decent chunk to you. It is the epitome of anti-magic trading tools, and is just plain stupid to play against.
Now the reason why his Q is stupid late-game is actually partially a problem with his E as well. Since so much of his burst is put into these two abilities, a Kassadin can essentially play like a ranged champion until he is ready to commit and one-shot somebody. A normal teamfight where you aren't oppressively ahead or chasing will involve you using your R to get into QE range and then just spamming the shit out of QE until your desired target dies from it, or is slowed enough to die from a teammate. Because of this, his risk isn't that high since he'll still threaten you greatly from a long range without putting himself to any real risk.
If Riot really wants a solution to the problem, they need to rework his kit to basically get rid of his current Q and remove some of the damage emphasis from his E, but if they want a faster, less permanent solution, they can just gut his Q and then buff the shit out of his W/ult damage so that he actually has to commit to a fight to be a threat.
tl;dr Kassadin's Q/E combo makes it too easy for him to play as a ranged champion with zero risk and this needs to be nerfed moreso than his ult if Riot wants to deal with him
also nerf Kalista, thanks
I also realize that you don't deal that much damage just by spamming Q/E, but it's an option for if you can't go in.
Ult
It's .05 less than
skillshot shuriken
Ult
It's the same as a
ultimate cannon laser
doesn't even have a ratio that high.
doesn't even have a ratio as high.
. His burst is low, his mobility is gated REALLY hard already, he is easily countered, and he doesn't actually scale as hard as people seem to think. His current kit is rather pathetic, and seems more suited to a bruiser instead of an assassin. Riot is gutting him when he is already a weak champion. His high win rate in the LCS/LCK is because a coordinated 5 man team can plan when to pick him best and knows exactly how to force him to snowball hard enough to carry before getting outscaled.