Hi guys, I'm pretty new here and this is my first champion guide but I hope that you don't rate me too hard.
However, I'm here to introduce Cassiopeia, one of my favorite AP carries in LoL. A lot of people think that Cassiopeia is underpowered but she is one of the most underestimated heroes in the game with her combination of spamming AoE-damage and her awesome AoE-stun.
Honestly, she was hard to play for me in the beginning but the more I played her the more fun it was.
If you like spamming your enemies with annoying DoT's and supporting your team with an AoE - stun, Cassiopeia is the right hero for you.

- AP for early harrassment
- Magic Penetration for higher DMG
- Increase for abilities
Greater Seal of Vitality - More life for a higher chance of survival
- Armor... ...you know why

My runes are very similiar with the other guides and many people I know often use runes for mana regeneration or movement speed but I'm convinced that a good early game is most important.

- Cassiopeia's passive is perfect to spam your DoT's without any mana problems but you have to be careful with that during the early game.

- The first ability I skill deals a lot of damage in a little area.

- It slows the enemies and poisons them for a few seconds. Can also work as ward...

- Twin Fang builds a great synergy with any "poisonous" Heroes like Teemo because you can cast it almost immediately if you target a poisoned enemy. It's the second ability I skill because of that.

- Cassiopeia's Ulti is just awesome, it deals tons of damage and can set a whole team fight with the AoE stun but you should be sure when you use it.

Pros:
-> awesome Solo-Laner
-> very low CD's
-> no mana problems
-> high range
-> high Damage output but not as burst

Cons:
-> squishy
-> dependent on team mates
-> hard to play
-> less nuke potential cause of the DoT's

- One of the best Summoner Spells of the game. Instant escape and nothing else causes an annoying "IN UR FACE"-effect like flash.

- Awesome against heals and as finisher...

I start the game with Q and to survive the early game easily.
As soon as I reached LVL 2 and skilled I start to harrass with combo of Q and E as much as I can. If I got a kill or an assist, I go back to base and buy some boots. Continuing with Tear of Goddess which is an important part of my build because of low CD's, you won't get ever OOM.
Through the mana you can also use your Q for every minion group because is perfect for farming and jungling.
After arriving LvL 6 you should try to gank when your "lane-enemy" is not there. Instead of I buy RoA to be more tanky and then continue with .
Additionally, you should ask your jungle for the blue buff because Cassiopeia just rocks with the blue buff and you can keep spamming Q and E as long as you want.
By the way, use strategically to uncover the right brushes and to keep distance to enemies. Here is very helpful and increases your lifepoints.
Finally, finish your build with and and you become extremely high damage dealing, tanky AP carry.

I hope you try it by yourself! It would be nice if you rate or comment my guide to give me the chance to improve my LoL skills...
Have fun, your JoKe95!