This is still a work in progress and I can only work on it when I'm in my graphic design course, so be patient

Cassiopeia is one of the strongest kiters in the game. Her multiple DoTs seem to turn people away from her, as if she does no damage at all, however, she can harass lane without much mana cost and do amazing damage for hardly any work. The one thing people should know is that YOU MUST LEARN TO SMART CAST. There is no way out of it. The default keybind to smart casting is Hold Shift + (insert skill here). With this, you can hover your mouse over the enemy and cast twin fangs repeatedly without having to take breaks in between casts(other than re applying your poison). This guide will show you how to position yourself in team fights, tips and tricks, laning/farming, and champions that compliment her. This is my first guide so critique it as much as you would like. Happy snaking :)

Pros

• Great Team Fighter
• Amazing ultimate if landed properly
• Brings a lot of utility to the table
• Great AoE Damage and Single Target damage
• One of the best kiters in the game, can get out of bad situations fast
• Synergizes with double AP carry teams
• Great Farmer
• Extremely Fun
• Voldemort's Hot Wife

Cons

• Extremely fragile until you get items
• Has no natural escape mechanism(excluding Speed boost from Noxious Blast and speed slow from Miasma)
• May have a tough time at solo top
• People will call you a noob for nuking with your multiple poisons

Expect to be placed in mid. If you can't handle a solo lane, you shouldn't be playing Cassiopeia. Once you gain one level in Miasma, throw it down on the caster minions and use one Noxious Blast on them. This should clear the creep wave. When you have enough AP/Mana/Mana Regen you can do this on every creep in the lane due to Deadly Cadence. Let's take a comprehensive look at the generic faces you will be seeing in mid.

Malzahar: I haven't played as Malzahar once, but I know how they function. You want to harass him and zone him out of lane before he gets ultimate, because when he does, you're going to be filled with anxiety once you enter the lane. If you can't manage to land a kill before he turns level 6, tell your jungler to burn his flash and let him ult you when you two are alone. Then follow up with Petrifying Gaze and start nuking him. If he begins to run, you can try to finish the kill without Exhaust, but if you can't, just use it. Start out with Boots and Three Health Potion

Brand: Brand is still a tough cookie to lane against, even after the so called "Nerfs", the only good nerf to him was the reduced range of Conflagration. However, as of now, Cassiopeia is a direct counter to Brand. Wait for him to blow his Pillar of Flames and go in, make sure you can kite his Sear. Pro tip: Use your Noxious Blast right before you think he's going to toss it, with this you gain some movement speed and you can easily kite him. Brand is extremely slow too, use this to your advantage, farm from afar and wait for his CD's to burn. Then kick his ***. Start out with Boots to kite his Conflagration.

Karthus: Karthus will forever be my favorite champion, but that doesn't mean he is the strongest champ in lane. He's extremely slow in lane and the only thing you should be worried about are his skittles( Lay Waste). Other than that, you can farm way harder, harass way better, and stay in perfect health. Make sure to hide close to creeps so his Lay Waste doesn't do double damage. You can start out with Doran's Ring or Boots.

Kennen: Kennen is a big problem for me later in the laning phase. You need to deny him farm from level 1 - 6. Usually, a good Kennen will be extremely agressive when he first gets his Hextech Revolver and Boots. Be extremely careful because when he has ultimate, he is one huge stun bot. Even if you flash out, he can flash in or use his Lightening Rush to gain distance. I suggest playing extremely passive once he gets all skills, because after that, he can stun you as he pleases. Request ganks early on so you can shut him down and get a gold advantage before it's too late. Start out with Doran's Ring

Akali: If you're playing against a good akali, she'll have both parts of her passive proc'd, which can be very dangerous. If you're laning against her at top, i suggest brush control at all times, throw your Noxious Blast or Miasma in the brush as much as possible. When she uses Twilight Shroud make sure you toss Miasma AND Noxious Blast in there. The reason why you also use Noxious Blast is because if you hurt you, you gain movement speed. Try to deny her farm with your [[Miasma, place it in front of your creeps so you make her walk through it to get last hits. If she does this, follow up with Noxious Blast and Twin Fangs. Once she reaches level 6, she will be a problem. Keep distance, and try to remember the Cooldown of each of her kicks, i believe they come up every 30 seconds(without runes/masteries) and she is refunded one kick for every kill/assist she gets. Honestly, I think you should get Boots, either way though, Akali is a ***** in lane.

Mordekaiser: heuheuheueuheuheueh, Morde es #1! Just kidding..... I find that Cassiopeia is a nice counter to most morde players, they think they're invincible with their shield, but it slowly falls, and so does their hp. Right after he uses his Cone, follow up with your combo. It will be up in about four seconds, so rinse and repeat. He's not too hard to lane against. Start out with Doran's Ring here, you'll need to blast through Mordekaiser's shield.

Orianna: Now this girl is a trouble maker, however, i've had a Cassiopeia beat me in lane when i played Orianna once. Let me tell you what the summoner did. You need to know that Orianna does have amazing harass, but she also consumes a ton of mana. Even with a catalyst, it's hard to maintain. Most Orianna players toss their ball behind enemy creeps, and then aim it to which ever way their enemy moves. Be extra careful for this, this is where i got caught. Once you toss the ball to your location, and you dodge it or took some damage, UNLEASH YOUR COMBO. Give her all you've got, make sure you land a few twin fangs, don't fear her for she has no other spell besides E to bring the ball back, but she can't Q + W you, so you should be fine. You'll need Boots here so you can kite her Command: Attack and Command: Dissonance.

Annie: She isn't as strong as she used to be, in fact, she was never that strong. Make sure you're focused on her by left clicking her in lane. With this, you can check how many charges she has, annie needs 5 charges to stun, and then a white ring will appear around her. When you see this ring, be careful of her combo, it is very deadly. Farm from a distance, and destroy her before she gets ultimate. Start with Doran's Ring here, she can easily be out harassed with that extra damage + HP.

Rumble: Rumble is pretty ****ty now. He was nerfed to ****, but he still does decent damage. Try to make him overheat so all he can do is auto attack, after that just toss your combo on his face and watch his HP Bar fall. He was quite the harass however, so I suggest constantly landing your Noxious Blast on him. Start out with either, I've beaten rumbles in lane with both Boots and Doran's Ring.


I will fill in the rest of this when I get time.

The set I chose is what I usually use when playing her, however, I use another set of runes too. First I'll go over the first set.

Greater Mark of Magic Penetration: This should be obvious, the AP marks are pretty **** compared to the magic pen marks. With all of Cassiopeia's damage over time, more magic penetration is also needed because i do not suggest a void staff on her.

Greater Seal of Scaling Mana Regeneration: Cassiopeia generally wastes a lot of mana in lane, it's a given if you want to win lane. Doran's Ring + Maxed Perseverance + These seals should give you enough Mana Regen until your jungler hands you a blue buff or two.

Greater Glyph of Scaling Ability Power: Personally, I go back and forth with my glyphs. I used to only use flat CDR, but now after playing on the tournament realm, I noticed that AP per level is quite strong. It synergizes quite well with Archmage's Savvy and lets you hold your own against an agressive mid lane(i.e. orianna, brand, annie, etc.) However, CDR has saved my *** MANY times, so it is completely up to you on this pick.

Greater Quintessence of Magic Penetration: Another obvious choice, magic pen = damage, plain and simple. And since you're not getting a voidstaff, you want to take as much as you can get.

Masteries are normal AP Carry masteries that use mana.However, I am trying to pioneer this new Exhaust trend(I think The Rain Man stole the idea from me), so you can choose if you would rather take Ignite. We'll go into this more, but if you don't spec into the exhaust mastery, take whatever you want in that row to scale down into Tier 3 for offense. Max the exp mastery, this is crucial for solo laning. Don't forget your point in the increased flash mastery, and that should be it. Here is an in depth breakdown of the masteries:

Offensive
Archmage's Savvy : Get this for extra AP, enough said.
Cripple Get this if you take Exhaust, if you don't get Exhaust, just take one level in whatever else you want to descend into the next tier.
Sorcery: Take this for CDR and to be able to access Archaic Knowledge
Archaic Knowledge : 15% magic pen goes a LONG way, this is a must.
The rest of the offensive masteries are useless to AP carries, so disregard them.

Utility
Perseverance: Take this for the extra health regeneration and mana regeneration for laning.
Good Hands : Take his or anything else to descend into the second tier of the utility tree.
Awareness : You need this if you are playing a solo lane champ, if you don't carry it, you will easily get zoned.
Meditation : Get this for some of that extra mana regen in lane
Utility Mastery : This mastery is overlooked a lot in my opinion. When you finally get that first blue from your jungler, that extra 30% time bonus is going to really pay off.
Quickness : There are only two spells in this tier, and one of which only needs 1 point to max, so obviously take this. Also, Cassiopeia is a kiter, so speed helps a ton.
Blink of an Eye : Those extra 15 seconds reduced from the flash CD has saved my life mucho times, take it for sure.
Intelligence : Extra CDR once again is a very very nice thing to have, obviously take this.
Presence of the Master : Reduced CDR on summoner spells? Why would you not get this?

The item build I use lets you dish out tons of damage and provide a huge amount of utility with your built in slow + Rylai's Crystal Scepter + Petrifying Gaze(stun or slow). Doran's Ring is debatable to begin with. Depending on your lane opponent, you might to start out with Boots and three Health Potion, but if you can get away with a Doran's Ring, I highly suggest you do. After you recall for the first time, you should have enough money for Boots + cata(or part of it) or Doran's Ring + part of Catalyst The Protector. Rush your Rod of Ages as soon as possible, for it will let you farm safely in lane without having to worry about mana(even without blue). Next, finish your sorcerers boots, this will increase your damage very heavily. Snag a Hextech Revolver, Rylai's Crystal Scepter and a Rabadon's Deathcap ASAP. Finish your Will of the Ancients and make your last item extremely situational, but usually I end up with a Banshee's Veil.

Some people choose to max Twin Fangs first, I don't. If you can't keep your poison up, then twin fangs is useless. You can max Twin fangs first, but I don't think you will put out enough harass in lane. Blah blah next section~

Flash is literally a MUST on summoners rift, not on dominion though. But this guide is designed for SR, so take flash on every champion you play, I don't care if you have a blink, TAKE IT. Also, it's very nice to flash + Petrifying Gaze into a team fight.

Personally, I take exhaust over ignite, and here's why:

Ignite does 50 + 25(X level) in true damage over 5 seconds. The only time I would recommend getting this over exhaust is when you are laning against a Dr. Mundo or Swain. Exhaust on the other hand reduces the targets AD by 70% and their Ability/Item damage by 35% and it ALSO slows the target by 40%. This obviously out weighs Ignite late game for sure, but Ignite can get you an easy first blood, so it's up to you.

• If your enemy jungler starts at blue, usually it will respawn at about 7:15. Drop a ward at the 7 minute mark and attempt to take it/kill him if he is low hp
• Noxious Blast only gives you boosted movement speed when you land it on an enemy champion, not minions, dragon, or baron.
• When fighting 1v1 Use Miasma to trap and slow enemies, follow up with a few Twin Fangs and then use Noxious Blast. Rinse and repeat this step
• You shouldn't be the one initiating, however, you can go in with your tank when he/she initiates. For example: If a Leona on your team gets ready to initiate, let her use her AoE stun before you use Petrifying Gaze. You can stick close to her, but don't get peeled off.
• Pick off squishes in team fights, keep everyone poisoned all the time and try to get a Singed on your team. All poisons in the game count as poison applied by Cassiopeia, so if your singed runs ape **** gets them all poisoned, you can just spam Twin Fangs the whole fight and nuke people.
• You can dish out tons of damage in lane, don't be afraid of harassing your opponent. One of the biggest problems people have with Cassiopeia is that she can't burst as much as the average AP carry. However, this is a blessing in disguise. If you were to toss down your Miasma behind your opponent, follow up with Twin Fang spams and Noxious Blast/ Twin Fang Spam