You can still Void Walk away from Ryze with it still on you, but you're still stuck to the ground. However, you can easily just use Void Walk blink through a forest wall (if you're close enough) and then escape. If you're so 'concerned' about Ryze or Morgana rooting you, just get a Cleanse. I never do, but I've heard its useful if there happens to be any form of movement disable on the other team.

My playing style with Kassadin is slightly similar in rune and mastery aspects, though I usually use Glyphs for cooldown instead of mana, then mana or movement speed in the purple runes (forgot the long-ass name). I usually try to work towards lich bane first, but I also get rod of ages. The +25% ability power ring is also quite powerful too. I rarely get any boots, even the initial set, before my first rod, the Void Walk is just so conveniently powerful. Usually upgrade to Tabi for the dodge and armor, no need for ability power with the rods. I sometimes do get the ability power boots though if it's a bit tough farming in the part between early- and mid-game.

try him with philo stone, sorc boots, trinity and guinsoo. Rapes and is easy to farm. I get a frozen heart after all that if lots of physical damage on the other team. If mostly casters grab some magic resist.

Trinity + guinsoo is amazing on kass. Sometimes you can run into mana problems but I personally am fine with how it goes.

i always get mercury's on a lot of heroes (including kass) since the snare reduction is too good
and don't tell me "oh you have riftwalk" because if you are slowed and running for your life that 40% reduction is going to help you a lot more than that puny +ap

has anyone noticed a bug with his riftwalk since the patch? he sometimes kinda glides to his teleport location instead of just appearing there

it's caused by lag i'm pretty sure of it

The 2 things i dont like about him though are his passive and his mana drain. The amount gained is so small, and the atk speed is nearly worthless as well.

Solution: switch the 2

Passive: Mana drain 3% of targets mana

Active : Increase attack speed by 10/15/20/25/30%

The mana drain works on creeps. Good for filling up on the siege and caster minions. Also late-game both of his passive abilities are VERY powerful.

I don't know I havent seen much effect from either late game, but that's probably because i build mostly on AP, and don't have mana problems past level 14 or so. Either way, i think hes one of the more solid champs out there

agreed, i love to play him, fits my play style really well, and he's been finding a spot on some teams for his disables. Usually i play the roll of initiator, so i usually stack HP and MP then AP. I hope to see his 'E' get buffed

they should probably do 5 casts (since 4 was too little 6 is too much in my opinion) E is fine as a skill still however
i also initiate as kass, his passive really makes a difference