“Don't stand in the W. Don't stand in the W. Don't stand in the W.”
“Cassiopeia is a ok match up. The only problem is, once you've gone in, you really need to commit for the kill otherwise she will out DPS you. Reason for this is when you go in with your W, Cassio can then place her W on your W image and will ground you. So, if you ended up going back on your W, this will allow her to get an easy Q-E spam on you. Either wait for her W to go on cooldown or all in her.”
“If she hits her Q, I'll wait for the movement speed burst to fade before using my Q. If I hit, I'll follow up with AA-E-AA; if not, I'll W and walk away. Mercury's Treads are a good buy here if I'm losing lane, and can get them really early - Lost Chapter > Merc's > Luden's Echo. After 6 if she's trying to chase me down, I won't risk turning around to Q since she might use that time to stun me with her R. Also if I'm getting low on HP I'll Flash immediately and not give her time to cast W and ground me.”
“She does damage, is fast and no cooldowns. Take Fleet or Grasp and trade when she misses her Q.
Best tip is take Fleet and TP, start Doran's Shield and just farm until Sheen and beg your jungler for ganks.”
“Skill dependent matchup pre 6. Be careful of her All in level 2 as she can all in you if she hits a Q. Level 6 is easy but one thing to note thats VERY important is instead of doing your normal E-W-Q-R Combo you want to do E-Q-R first as she will try to R you while you have your R active. By doing this combo you can W behind her while R'ing to avoid getting R'd.”
“Cassio can screw you over with her miasma, making you unable to use any movement abilities/summs including Q3, E1, E2, R and flash. Her ultimate will stun you on the spot if you're facing in her direction, and she will shred you to pieces with twin fangs if you're poisoned. Rush tier 2 boots asap so you can dodge her skill shots more easily. If her miasma is up, you want to go for super short trades where it won't screw you over. Go in with E + Q3 and then hit her as much as possible before she's able to use abilities again, and BACK OUT with E2 before she uses her miasma. Her miasma has a 24 second cooldown early game. Cassiopeia maxes that spell out last, so your E will end up being on a much lower cooldown. With the second engage you can go for the kill. She will most likely use her ultimate when you're going for the knock up with Q, so MAKE SURE to turn around. It will only slow you instead of stunning. If you succeed in doing that, then you're going to win all the trades. If you get stunned by your ultimate, there's a super high chance that you're dead. She will follow up with miasma so you can barely move and then kill you. ”
“Start Doran + 2 Pots if 1) You think you can outplay her and hit your W's to generate a kill at levels 3-5 or 2) You think she will burst you down post 6 (get an extra ring).
Start Corrupting if you think you will not hit your W's (or you will get poked down) and you rely more on wave clear/spammy poke (you will be way more squisher but more durable -- this is recommended if you are sure you will not get hit by CC spells and instantly die).
Rather difficult matchup if it's a very good Cassio. Early try to get boots as fast as you can to dodge as many Q's as you can (since Q enables her). You can play the range advantage with your Q but if you get close be careful since her movement speed (phase rush maybe) can make you miss your W.
Her ult is highly predictable and you can dodge it if you turn around right when you see the animation starting. (You need some practice for this but in time it becomes easy). The impossible thing to dodge is the R->Flash ult - so keep in mind that a good player might do that to kill you. A good player might also try to kill you pre 6 and kick you out of the lane. If you hit your W E Q's combo you have a good chance at winning but otherwise I'd just push and roam because it's a rather annoying and difficult matchup (kind of like Azir).”
“Early levels cassiopeia is pretty mana dependent, so you can make her waste mana and health. She cannot really trade with you unless you let her hit Q. You will win all trades unless you get hit. You can freeze the wave early and you kinda out range her after level 3. She also has a bad early which you can abuse. After six, you can dodge her ulti with a simple hidden shadow combo. Keep in mind, she has really good scaling so don’t let her farm up and become a menace. Keep in mind her W gives her free stun if you ult her. So make her use W first before all inning.
“Runa Recomendada: Eletrocutar.
Cassiopeia usará o Q na Katarina nos níveis iniciais ou AA+E e é nesse momento que você precisa tomar cuidado para ela não crescer no jogo, pois caso ela tire muito de sua vida nos níveis iniciais, poderá morrer com facilidade. Katarina pode jogar agressivo contra Cassiopeia no nível 2, mas só deve agressivar caso Cassiopeia errar o Q. No nível 3, pode agressivar com EW+AA+QE+AA caso ela erre o Q, mas precisa tomar cuidado com o W da Cassiopeia e se reposicionar assim que o cooldown do Q da Cassiopeia voltar. Depois do nível 6 ou da Hextech Gunblade, basta você agressivar com o combo, olhar para trás e ultar nela. Cassiopeia não terá como petrificar Katarina com seu R e você ainda estará ultando ela. Caso ela perceba que você fez isso e use flash para trás de você para usar o R, olhe para o lado oposto para negar a ultimate dela, e se reposicione pois sem a ultimate talvez não consiga finalizá-la. Em teamfights, fique atento ao W e ao R da Cassiopeia, principalmente o flash+R, pois poderá te impedir de fugir ou poderá te prender até a morte. Foque-a assim que puder visto que seu dano é alto e é em área. O potencial de perigo de Cassiopeia é de igual para igual visto que Cassiopeia possui muita velocidade de movimento, muito dano e muita cura, além de impedir que Katarina fuja usando seu W ou R. ”
“Scary snake lady punishes mistakes really hard, if you miss an E while in range of her Q or make a mistake with your R you're pretty much done for without Flash. If she takes Cleanse she can also pummel you even if you do hit the E. Great at level 2, scales like a monster and hard to punish if she's good at her champ. However not 100% unwinnable, as she is still immobile and can be shut down by roams.”