Kassadin

His ap shield will win him trades and his E ability will make you not want to use your W on minions to farm so yeah, he's a strong counter, also outscales you HARD.

Lissandra

Pretty much unkillable and is ranged so it can poke you easily while always being safe, you should try to roam and get kills elsewhere

Rumble

Has a shield and easily out-trades you because of his slow, if jungler helps you kill him 1 or 2 times only then you'll be able to oneshot him when you have 6.

Lux

Pretty much any unmobile mage is going to be an easy matchup for fizz, since they can't dodge and neither can kill you, just be aware of her Q

Veigar

Annie

Twisted Fate

Dodge yellow card with your E and ur good, he doesn't have mobility so from lvl 6 on should be easy to kill, only problem is the roaming.

Seraphine

immobile target you can oneshot...

Brand

Xerath

Just dodge his stun and you're good, poke is dodgeable and you can burst him from lvl 6 on.

Katarina

Vel'Koz

Ahri

Won't kill you if you dodge her charm but you won't kill her post lvl 6 because of her ult and high mobility.

Orianna

Annoying pre lvl 6, but easy to kill after, dodge her ult with E, dont use if you can't one-shot her with ur combo

Viktor

Pretty much the same as orianna, annoying pre-6

LeBlanc

Skill matchup leblanc favored.

Diana

Has the same or more burst than you and has a shield, if jungler helps you get her behind you crush her.

Vladimir

Pretty much unkillable for you since he has sustain and can go untargetable to dodge your R. Roam and get oblivion orb.

Sylas

Lots of self heal and dmg, you need to use your E when he has already used his dash or else you won't land it, rush oblivion orb or you'll only be able to kill him when you have ignite.

Galio

Ap shield will soak your dmg and he will have enough dmg to burst half your hp or even more with his full combo.

Akali

Dodge her E, she'll dodge your abilities aswell, pretty much none of you will be able to kill each other if both play at the same level, if she uses her W it has a long CD so thats the best moment for you to trade.

Ryze

Pretty much even matchup, you should kill him easily since he doesn't have that much mobility, but a good player can zone you out in laning phase.

Hwei

He will try to just farm most likely, he doesn't have the dmg to kill u in early game but has some options to CC u and keep distance.