-Finishing up Pros/Cons.
-More ability order information.
-Better explanation on items/runes/masteries
-Explanation on her abilities
-Build 2

Hello, thanks for taking your time to look at my first Cassiopeia guide.
In this guide i will be explaining a few obvious things such as:
- Runes
- Skill Order
- Item order/ and why to buy those certain items.
-- In-Depth Item explanation
-Skill Sequence

And so on. So please, read on enjoy, and i'll take any constructive criticism you can give.

Please do not vote at all if you have any advice or criticism; just leave it in the comments below.
It was published on accident.

-Lore-

While her sister Katarina has always been the most celebrated member of the household, the Du Couteau family has a long history of service to Noxus. It has often been said that no soldier has ever been as fortunate as General Du Couteau to have been graced with daughters. His youngest, Cassiopeia - despite lacking her sister's killer instincts - was equally renowned in at court for her stately character and elegance. Cunning as she was beautiful, the temptress could never be found far from the arm of any foreign dignitary, her wiles prying secrets from the lips of even the most wary attaché. With the Noxian barbarian pacification campaign having ground to a standstill, Cassiopeia had set her sights on a diplomat from a tribe of the Freljord region. Thinking him an easy mark, the scheming seductress set about beguiling him. He refused to confide in her, however, until she swore an oath of secrecy upon his sword - a strange weapon with a serpentine curve to the blade.
Once her tryst was over, Cassiopeia provisioned her father with information regarding the barbarian resistance. As she divulged this intelligence, a wave of revulsion washed over her. She screamed in agony as her silky skin hardened to scales, her lustrous hair thickened to leather, and her manicured fingernails sharpened to claws. Dazed, she fell upon a group of horrified servants, rending them limb from limb in a heartbeat. When it was over the blood soaked figure was no longer the ravishing jewel of the Noxian court, but a horror trapped somewhere between woman and serpent. Unable to serve in her traditional capacity, Cassiopeia departed for the League, continuing her service to Noxus on the Field of Justice.

-Observation-

Cassiopeia glides along the marvelous hallway with unnerving grace, the scrape of scale on marble announcing her passing to the empty corridor. Her elegant curves and stately posture combine to form an appalling juxtaposition to her serpentine body. The exquisite features of her face, wreathed in a cobra's hood, bears a look of chilling determination, while a serpent's tail conveys her expediently onward towards her destination.
She pauses for a moment before a pair of grand double doors, the relief of a panther marking each one. Above the doors, carved on the stone archway, is an inscription: "The truest opponent lies within." Her eyes narrow as she reads the engraving.

Cassiopeia stretches a taloned finger towards the door. It parts effortlessly at her touch, swinging open into blackness. She peers hesitantly into the black for a moment before composing herself and gliding inside.

REFLECTION
She found herself in her chambers in the Noxian estate she called home. An elegant curtain ran across the center of the room; a shroud against prying eyes. There, through the lace, stood the unmistakable figure of her father, General Marcus Du Couteau. She stared at him longingly, admiring everything about him, from his stately military garb to his perfect soldier's posture.
He stepped forward, extending a hand towards the partition. There was moment of panic. No matter how many times she allowed her closest family to see her, she was always overwhelmed with anxiety and revulsion.

"Don't look at me!" Cassiopeia lamented.

The General froze for a moment. Then his voice took on a sterner character. "You are my daughter, Cassiopeia. And you are beautiful."

"Liar!" she hissed, turning away. She could hear the rustling of curtains as he approached.

"Daughter, look at me", he implored. Reluctantly, she complied, wiping away her tears with a viciously clawed hand. She did not speak.

"Cassiopeia", he went on, taking a step forward, "I have been summoned. It is a grave matter, but one that I cannot refuse."

"Take sister with you. She can keep you safe", she sobbed.

Marcus shook his head, "Katarina cannot return. The matter with Ionia has not yet been settled, and her duty to the League compels her to stay."

"Father, if you do not return, I will be alone", she stated.

The General reached out to touch his daughter's face and she recoiled, turning her back again. His voice turned colder than iron. "You are a Du Couteau, Cassiopeia. You have served Noxus, and she cares for her children. You will never be alone." He paused. "One day, you will remember your duty."

General Du Couteau took her hand and pressed a sealed letter into her palm, crumpling it slightly. "Should I not return, Cassiopeia, this will guide you and Katarina."

Hearing her father turn to leave, Cassiopeia panicked. She spun about, but found herself alone. She examined the letter in her hand. It was marked in a wax signet that she did not recognize, but the seal was already broken. She unfolded the page.

In blood red ink, someone had penned: "Transcendence Way, the Ivory Ward, 5:00 PM." Below it was a stamped image of a black rose.

The peals of a clock tower caught her attention, followed by the sounds of bedlam. All around her the household abruptly became chaos. Each passing footfall and gossiping whisper filled her with ire. There came a hesitant knock at the door. She already knew who to expect.

"Enter!" she commanded, her rage overcoming her revulsion at the thought of being seen. The door swung open, revealing one of her father's bodyguards. He entered slowly, staring intently at her silhouette on the other side of the curtains, his face a mixture of fear and shame.

"Mistress Cassiopeia," he began, "Your father has..."

She cut him off, "Spare me your excuses, fool! How did it happen!"

"We were in the market," he stammered, "Your father slipped away."

"And I ordered you to shadow him, did I not?" sneered Cassiopeia. She drew closer to the partition. The soldier looked away in shame. He did not answer. Cassiopeia sunk her talons into the hanging fabric, ripping it from its moorings in one swift motion and laying bare her monstrous body. "Speak, coward!" she commanded.

The bodyguard backed away in horror, blanching white in shock.

"What's wrong?" Cassiopeia teased, drawing one of her wicked hands to her face in feigned surprise. "Don’t you find me beautiful?"

She advanced, fastening her claws securely around his neck. She lifted his worthless body and suddenly, a shattered pocket watch fell out of his pocket. The watch's hands stopped dead at a quarter past five. "This was all we found," he croaked.

She caught her quarry's gaze in hers, his body shaking as she choked the life from him. His face was white as snow, but for some reason there was no fear in his eyes. Realization washed down the length of her serpentine body. Cassiopeia sneered. "Charlatan," she muttered, venom dripping from the words. "You force me to relive the moment I lost my father for your own sick pleasure?"

The bodyguard's face turned as implacable as his eyes. "Why do you want to join the League, Cassiopeia?" he inquired.

"My father is dead," she spat, "One of you knows something. And I will have justice."

The soldier nodded. "How does it feel, exposing your mind?"

Cassiopeia's looked him dead in the eye. "Curse you," she muttered emotionlessly. The figure dissolved in her grip, leaving only the darkness. The doors to the League swung open.

Pros

-Great Nuke combo
-Good poke in lane
-Can turn around a team fight in instant
-Can dominate any Mid champs if used right
-Low mana cost on abilities

CONS

-Squisy!
-If the team sees how much damage you do, you will get focused
-can die easily against many AD carries
-pretty hard to master

This is how i see it.
Build 1: When i made build 1, i was going for lane sustain and survivability, making it kind of "Noob" friendly, and a sure way of escaping ganks, and still being able to output a lot of damage early - late game.

Build 2- Just came to me. Great damage, decent survivability, taking advantage of Archangels, and your passive, deal more damage ( build 2 is for players with a more aggressive style, that are sure they can get kills in their lane )

Greater Mark of Magic Penetration - For that annoying tank that that gives you trouble and won't die. Every bit helps ^_^.
Greater Seal of Scaling Mana Regeneration - Way better then Greater Seal of Replenishment . Some people may say no; but the mana regen past laning phase is pretty awesome, even if it is a small amount.
Greater Glyph of Scaling Ability Power - Same reason as above, More AP Past level 6, go with Greater Glyph of Ability Power if that's the only AP glyphs you have.

Now; the last one is really up to you.
Greater Quintessence of Ability Power is really good, gives you more damage, but if you prefer Magic penetration, i would suggest Greater Quintessence of Magic Penetration

For Masteries i go 21-0-9. Taking the obvious masteries For a AP carry..

You might be wondering why i put only 2 in Swiftness and 2 in mediation. Well i find the 1% is helpful. But if you feel like taking the rest in mediation, you still have to put in some for swiftness; you don't have to put any points in this if you don't feel comfortable with it, since Noxious Blast gives you a nice movement speed boost, that is if you hit it.
The mana regen in mediation helps your early lane sustain, so long as you don't spam your spells for no reason..

1 point in Runic Affinity if you have a good jungler that gives you the Ancient Golem buff.

A point in Summoner's Insight for the small but nice flash cooldown.

The core build you should have

BUILD 1

And Either;

OR

BUILD 2

And Either;



OR





In-Depth Reasoning of these purchase's:

____________________________________________________________________________

After much consideration, I've Decided to Max Noxious Blast first, instead of Twin Fang.
I realized maxing out Twin Fang is really a really aggressive way to play, you can also get a more decent poke without wasting more mana.

Also Noxious Blast does more damage and has a .9 AP ratio; While Twin Fang has only a 0.55 AP Ratio, and does less damage maxed out, but I'll go more in-depth on that in the abilities section

When i use her, i take:
- Exhaust
- Flash
You're probably wondering, why the Fuuuuuuu.. is this noob using exhaust instead of ignite..
Well, let me tell you why.

I choose exhaust > ignite to make sure i get the kill, since her poison's are basically ignite it's self. When you take the mastery point Summoner's Wrath not only does that slow them, getting you a sure hit with your Noxious Blast it also reduces their MR, by -10, which really helps a lot.

If you're getting ganked, what i do is, ult both of them, exhaust the one that does more damage when my ult is about to run out, finish off the weakest one, if i'm low hp i'll run; or flash. If i'm high health i'll stay, fight, and hope for a double kill.

- Flash Obvious reasons, getting chased or ganked by more then you can handle, ult and flash away like ... *Puts Sunglasses on* A BOSS..

If you have any questions, concerns, or some constructive criticism that could help this guide be better, please leave a comment..

Hope this was good for my first guide, i'll be sure to update it when i become more advanced and skillful at making guides.

Changed Skill order to Maxing Noxious Blast first, and Twin Fang second.

Havn't edited this in a while sorry, im sick.