Just revert the nerfs on kassadin and change his ultimate
His identity DOES NOT have to be a mobile assassin, why not just rework him to be an AP bruiser instead of gutting him constantly?
3 Comments
You are correct, his identity does not have to be a mobile assassin, but that is what his identity is.
From what I've been gathering, Assassins are meant to do high amounts of damage throughout the game. When I look at Kassadin, he has the best escape in the game, the best chase in the game, and then he can put out great amounts of damage. He's a squishy champion, but you only need to buy a ROA and you're pretty much a slight tank. Through playing him I've been diving in fights, killing the ADC or whoever I need to kill and then I'd either Riftwalk out or I continue to chase with Riftwalk because I hardly took a lot of damage thanks to ROA's HP scaling. If they continue nerfing his damage he won't be a high bursting Assassin anymore, if anything he'd probably become 
.
Those are my thoughts on him so far from experiences with him.
yea he doesnt and Lee Sin doesnt hafta be a mobile fighter, Leona doesnt hafta be a high CC support, and Talon doesnt hafta be a high damage assassin... but they are and keeping them that way is what gives them their identity in league.
Fixing Kassadin is much better then changing him, he doest hafta be a mobile assassin, but he is and changing that would go against what Riot wants. Its their game and while our opinions matter to a degree, it is ultimately their choice in what they want to change, and they want to keep him a mobile assassin.