Talk:Kassadin/@comment-14081808-20141012004408/@comment-1330314-20141030065858

It's not so much about punishing use of power as it is about controlling it. People think Kassadin is meant to be omnipresent and able to jump freely across the map, and for a time he used to be able to do that, but he's not, even if you have the tools to make him feel like it. Kass can still exert global map pressure, and is still the best roamer in the game, but even with him, mobility isn't meant to be cheap. Being able to strike anywhere at any time, on demand, is already massively powerful and, like Soraka's healing, should incur a heavy cost. He can Flash every 3 seconds, which if left uncontrolled would allow him to enter and exit battle at will, and at much less effort than any other champion, which isn't a good thing: prior to his rework, Kass's ability to pop in, silence his opponent, kill them and pop out without them being able to fight back was immensely oppressive, and earned him the highest ban rate in the history of the game. Even now, with all the controls put on his power, he's nearly impossible to shake off once he gets a lead, and snowballs super-hard.

Bottom line, mobility is massively strong, to the point where even Riot underestimated its power and impact for a long time, and allows a huge amount of control over the flow of a fight and over the mobile champion's opponents. You cannot expect to give a champion near-unlimited mobility for free without screwing over everyone going up against them. Not even Kass gets to chase and juke for free, but he still has enough power in his Riftwalk to allow him enormous amounts of mobility in and out of combat, which he can recharge with Nether Blade. It's not so much about blinking around the map at will as it is about blinking in exactly the right situation, and putting Kassadin's godlike mobility to full use to jump across the map just when you need to.