Welcome to my in depth Cassiopeia guide! I'm Yeager, a high elo midlaner in league of legends consistently reaching at least master tier on EUW every season since season 5 and challenger EUNE since season 9. I spend some of my free time creating high quality educational content to help you improve and become a better player. Why should you play Cassiopeia? Cassiopeia is a mechnically difficult champion to pilot but also super rewarding once mastered. She is one of the absolute best scaling mages due to her insane DPS potential but also her passive that allows her to skip boots and buy 6 full offensive items. Her consistent damage and kiting potential makes her a solid pick into short ranged comps and especially tanks. Cassiopeia can also be played both mid and to plane, so if any of this sounds interesting, then this might be the champion for you.

Pros + Insane DPS + Huge outplay potential + 6-item lategame scaling + Very rewarding Cassiopeia has been among the strongest midlaners since item changes was introduced to mages. She has insane DPS and full 6-item lategame scaling thanks to her passive. It's a champion that will reward you based on your skill level, so you can always be relevant with her even when she's out of meta. If you invest time into learning this champion, you will find yourself climbing the ranked ladder much faster.

Cons - Immobile - Mana hungry early game - VERY High skillcap - Short range Cassiopeia's biggest weakness is her immobility and short range, making her weak into teamcomps with long-range abilities and strong disengage. She also has some manaproblems early on until you get Tear of the Goddess and Lost Chapter, so spamming abilities without managing your mana can cost you the entire laning phase. Due to her high skill-cap, it's a champion that can't be mastered from just 30 games, she needs lots of time and practice.

Flash Is a must-grab on mages like Cassiopeia because you're really squishy and require solid positioning. She does not have any built-in dash/jump, so 1 wrong move in teamfights can cost you a lot. Flash also enables the flash-ult combo.
Heal Used to be the standard summoner for most mages. It heals you and a nearby teammate, so if you are planning to skirmish a lot with your jungler, this is a viable option.
Ignite The go-to summoner for having kill pressure in lane. I use this one most of the time as it fits my super-aggressive playstyle, letting me grab some solokills in lane to scale faster, and take over the game.
Cleanse Underrated spell. If you are playing against a heavy CC mid + jungler, then you want Cleanse for sure. The benefit of having cleanse is the fact that you don't need to use a item slot on Quicksilver Sash, and can instead focus on buying your core items.
Exhaust This helps a lot against champions that rely on burst damage to finish you off. Champions this can be good into, are something like Fizz, Zed, Rengar, Talon, Ekko. Having Exhaust also makes your 1v1 splitpushing much stronger.
Barrier The more selfish summoner spell compared to Heal. It has lower CD and is a much safer pick against opponents with Ignite.
Ghost This used to be the best secondary summoner spell for Cassiopeia because it covered all her weaknesses. Due to the nerfs it's no longer a top-tier summoner, but it can still work in some situations.

Keystone Phase Rush: This is without a doubt the best keystone for Cassiopeia. It covers one of her main weaknesses - being immobile. She can chase, escape and kite better with the movement speed, and slow resistance from Phase Rush. This is the absolute best keystone on Cassiopeia. Tier 1 Manaflow Band: When fully stacked, we permanently get 250 bonus mana and a passive that restores 1% of missing mana every 5 seconds. It's not that great early game, but from mid game it can help a lot since Cassiopeia is very mana hungry. Tier 2 Transcendence: CDR is super important on Cassiopeia as she is a DPS mage that relies on spamming abilities. Her twin fangs needs a certain amount of CDR before she reaches the state of "machine gun cassio" Tier 3 Gathering Storm: Weak early on, but slowly ramps up. From minute 30 you will start noticing the difference this rune can make. Sometimes your team will get a huge lead, but since it's soloq, they will most likely fail to close out the game. This rune is basically the late-game insurance in case everything goes wrong. Alternative rune: Scorch is a early game focused rune that gives you more kill pressure in lane. If you are planning to carry the game by farming the enemy midlaner, this is without a doubt the best option with Ignite as you have way more kill potential in lane as Gathering Storm won't really kick in until 30 minutes. Tier 1 Taste of Blood: The extra sustain from this rune can help us stay in lane longer and get our core items. It also helps when trading as you get some HP back. Tier 2 Ravenous Hunter: This is one of the best lower tier runes from the Domination tree. The amount of healing you get lategame is just insane, especially because her Twin Fang is single-target with low cooldown, so you get the FULL healing from this rune. This combined with her built-in sustain, will get you back to max HP in no time.

PASSIVE ABILITY

Serpentine Grace (Passive): Cassiopeia gains Movement Speed per level, but she cannot purchase Boots items.

Q

Noxious Blast (Q): Cassiopeia blasts an area with Poison after a brief delay, granting her increased Movement Speed if she hits an enemy champion.

W

Miasma (W): Cassiopeia releases several clouds of poison, slowing, grounding, and lightly damaging enemies that pass through them. Grounded enemies cannot use Movement abilities.

E

Twing Fang (E): Cassiopeia lets loose an attack that deals increased damage to Poisoned targets and heals her for a percentage of the damage dealt. If the target dies from this attack, Cassiopeia regains Mana.

R

Petrifying Gaze (R): Cassiopeia releases a swirl of magical energy from her eyes, stunning any enemies in front of her that are facing her and slowing any others with their back turned.

Twin Fang is maxed first as this is our bread and butter ability. It's our main source of damage and sustain, but it's also used to farm creeps since it refunds mana every time you last-hit a unit with it. Noxious Blast is maxed second. This is where the great chase-potential comes in for Cassiopeia as it gives movement speed when you hit a champion. It's great for poking and kiting champions while shredding them fast with Twin Fang. Petrifying Gaze is maxed third. Great ultimate that allows Cassiopeia to solocarry in teamfights. We put a point in this whenever we can for the lower cooldown and more base damage. Miasma is maxed fourth and last. We only put a point in this ability early to have the slow + grounding effect so we can stop mobile targets and lock them in place.

Doran's Ring

Doran's Ring: Solid starting item for most mages as it gives a decent amount of HP, AP and mana regen. This is rarely bought over Corrupting Potion on Cassiopeia but if you won't be interacting with your lanter at all, then this is a decent option.

Corrupting Potion

Corrupting Potion: This is the most bought starting on Cassiopeia because of the sustain and early-game dueling potential. Having this item means that you will never have to buy Health Potions so you already save a lot of gold.

Morellonomicon: Buy this against heavy healing opponents like Swain, Vladimir, Soraka and so on. This is also really good against ADCs because you can counter their self-healing from lifesteal items.

Banshee's Veil: Provides some some CDR and AP which Cassiopeia loves to have, but it also gives MR and a spellshield for "flashy" champions. I buy this against for example AP Gragas and Annie, because they rely on catching people off-guard with Flash+combo. This item counters them completely.

Zhonya's Hourglass: If you are facing a heavy AD team, or just AD assassins, this item will save you a lot. Rush this item 2nd against Zed because we need the active to counter his Death Mark. Against for example Talon and Kha'Zix you can get away with just building Seeker's Armguard and then upgrading this item last.

Quicksilver Sash: This is a must-buy against Malzahar and Skarner, as it is the only item that cancels Suppression. I only buy this item to counter Suppression - for everything else you should get Cleanse, so you don't have to use up a item slot.

In the early game you may have to play a bit more passive against some of the meta picks. Cassiopeia is really mana hungry until she gets tear, so you should avoid extended trades unless the target is within kill range. Use your Twin Fang to last-hit creeps and keep the wave at your side, so you can avoid getting ganked by the enemy jungler. Your main goal in the early game, is to have enough gold for Tear of the Goddess and a Control Ward. Once you have enough gold, you should shove in the wave OR freeze it, and base for your items. When you have Tear of the Goddess you should always use Twin Fang to last-hit creeps so we can get some free mana and stacks. Since we now have a mana item, we can afford to play a bit more aggressive. If the enemy is overextended, you should go for trades with Noxious Blast + Twin Fang as she can shred people really fast, and often they won't be able to trade back because of her DPS, and the mobility she gets from Phase Rush. Enemy junglers often camp Cassiopeia because she has no mobility. You can play aggressive if you have proper vision, but you still need to be aware of possible ganks. Always have a Control Ward in one side of the lane, and play around your vision.

At this point you should have at least Liandry's Torment. Seraph's Embrace and Rylai's Crystal Scepter. If the enemy is not respecting you, you can play super aggressive and look for kills with Ignite. For a almost guaranteed hit, you should wait using Noxious Blast until the enemy midlaner stops to auto-attack a minion, and then run them down. There are not many midlaners that can match Cassiopeia's DPS at this stage of the game, so don't be scared of taking trades. If the enemy midlaner is playing too passive, you should just shove in the wave fast and look for roams, or stealing away objectives/enemy jungle camps. Cassiopeia can kill dragons really fast with her insane DPS. If you somehow end up on the losing team, don't lose focus because Cassiopeia outscales most midlaners lategame! Try stalling the game by clearing waves with your team until you are strong enough to carry. People always make mistakes when they are ahead because 1. They think it's won and lose focus and/or 2. They don't know how to close out the game. When they keep making mistakes and get punished for it, they will eventually get tilted, and that's when you can turn the game and make a comeback.

Late game is where Cassiopeia truly shines. For a mage, she has unmatched single-target DPS that will shred anyone who's within range. She also outscales most champions because she can build 6 full damage items! Late game for Cassiopeia is all about objectives and teamfights. As Cassiopeia you pretty much want to be constantly grouping with your team at this stage of the game. You can still go to other lanes to pick up big waves, but you should avoid splitpushing most of the time. The way you play cassio in teamfights is the same as most other mages. You need to stay with the backline because you're incredibly squishy. Use your Miasma and Petrifying Gaze on the enemy frontline to lock them up, so they won't be able to use any mobility spells. The good thing about Cassiopeia is the fact that she shreds tanks REALLY FAST due to her insane DPS. Twin Fang. Keep looking for opportunities where you can take big objectives like baron and elder drake. Cassiopeia can shred them really fast, so you must take advantage of this by constantly clearing out enemy wards and hovering around objectives.

Noxious Blast
- can be used to check bushes for targets. If you get movement speed when using it, it means a champion is there.
- The ability has a small day. Try predict where the opponent is moving before you use it.

Miasma
- Enemies who are caught in this won't be able to use flash or other movement abilities. Use this to lock down high-mobile targets before you unleash your full combo.
- Has a minimum cast range, so it can't be used in melee range.
- You can W + flash

Twin Fang
- The ability deals more damage on poisoned targets. This includes the poison from champions like Teemo, Twitch and Singed.
- Make sure to almost move around and not stand still while using Twin Fang. Doing this helps you dodge abilities and reposition better for your next Noxious Blast.

Petrifying Gaze
- The first basic trick on Cassiopeia is the Petrifying Gaze + Flash. It's the same as other ability + flash tricks where you ult in the direction you want, and then flash right after the cast time. This will catch a lot of people off-guard and can net you a lot of solokills.

Freezing is a advanced technique that lets you deny your opponent exp and cs if done correctly. Freezing a lane means that you kite/tank the minions without letting your tower hit the creeps. You need to make sure the enemy minions always beat yours. After the enemy killed your entire wave, you let 2-3 of the enemy creeps live, and kite them until the next wave is here. When the next wave arrives, the wave will freeze right outside of your turret range.

By doing this, you are safe from jungle ganks, while your opponent takes a big risk everytime he overextends for a cs.

You can Freeze the wave when you and the enemy are even or ahead, and it can be used to help you win back the lane after you screwed up and died. You can attempt to freeze the wave already from level 1, leaving your opponent vulnerable to jungle ganks or be within your kill range, if you are able to kill them. When you get a lead, and you can solokill an overextended enemy laner, that is exactly when you want to freeze the wave. You force the enemy midlaner to either be in your kill range, or miss a ton of cs and exp, putting them further behind.

Freezing a wave is a great way to snowball a lead, if you have no objectives to fight for, such as dragon, herald or towers.

Here is a youtube video that explains wave management very well. I recommend watching the entire video. All credits for this video goes to Blitz Esports LoL

That's it for my Cassiopeia guide. Thank you so much for reading it, i hope you found the guide helpful. If you still have questions, feel free to post them in the comments, or on my stream and i will get back to you ASAP!

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