Hello!

My name is SOTH and I am here to share my thoughts about the post-patch Kassadin.
I have mained Casa Dean for quite some time now and he is the champion that i always fall back on when in doubt in champ select.

This Outside of the box guide will show you not only how to build Kassadin smart but also understanding the champion!

Some may notice the lack of boots in my guide. The lack of mana? And the lack of durability? Fear not! This will be explained later in this guide!

Kassadin should be played as an ap assassain staying calm and farming until level 6 where he should almost always go for a kill. Kassadins playstyle is based on the Riftwalk It's an amazing spell that makes it possible to catch up, deal #tons of damage and get away unharmed. But use it smart! using it to do damage in a teamfight for instance is not clever. It makes you an easy target and you will instantly be killed (and that is not the goal with this guide, duh)

Keep in mind that you will have to change your playstyle to suit this build. You will run out of mana earlier than usually and due to this you need to be more careful about your jumps, but in exchange you will have massive damage instead!

Also make sure you have your escape planned before jumping onto someone. It's for example really easy to make auto attacks or spells on a kassadin that has recently done his full combo on someone and is now walking slowly away due to bad planning. This will often cause the Kassadin just as much pain as he dealt.
This can be avoided though with the help of Ignite, Exhaust, Flash or Heal but the optimal action would be to kill the enemy instantly.

Kassadin excells at:

KILLING EVERYONE!

Staying mobile even without boots.

Keeping his mana up with his nether blade

Being an extremely fun champion to play! :)

Staying durable, even with squishy build.

Kassadin is bad at:

Farming from afar (not really)

Escaping after using Riftwalk to do damage (don't do that)

Lack of mana

Wave clear

Kassadin is extremely mobile with his Riftwalk! (i guess that's why he is so fun to play) And because of this you don't always need boots for kassadin. Especially because of your core item, Lich Bane increases your movement speed from 350 (base) to 367 which is to be fair still low, but remember that you can get any item instead and jump around with your Riftwalk

Sometimes you will want to get boots though. There is not many great cdr items except for Ionian Boots of Lucidity and Deathfire Grasp. And Kassadin likes CDR! ( Riftwalk on 1.2 second cooldown :3 )

Use this information to judge if boots is a smart buy or not.

After the Kassadin rework, it became a standard to build the Mana Cannon Kassadin. This is a well known build based on the Archangel's Staff and stacking the Tear of the Goddess.
But why?
Building Mana only because your ult deals damage based on your mana is not a great idea. It's the only spell that scales with mana, and it's a spell leaving you helpless face to face to an enemy that doesn't care about your 2% mana scaling.
Say you manage to get around 3000 mana. It's only going to do 180 damage after four previous Riftwalks. And by then your mana will be drained :/

Mana Cannon Kassadin gives you the ability to spam Riftwalks though, but in my eyes it's a stupid build :(

Rod of Ages is an excellent item that brings both durability, mana and decent AP to the table. Sounds like Kassadin right? But after loads of games with the Voidwalker i have decided to ditch the RoA and go full AP Kassadin. We like to live dangerously, don't we?
This is fully doable since his passive Void Stone makes him take 15% less magic damage! (op)
Imagine a Javelin Toss lands on you. 700 damage on anyone else (if no magic resist was built) But Mr. Troll Kassadin takes only 595 damage (huehuehue)
And we don't need the mana for reasons explained in chapter 5: Mana Cannon Kassadin?

Therefor there is no need for it anymore since the AP ration is way to low for Rod of Ages to be worth the buy.

Spam W to last hit.

Remember that Nether Blade (W) resets auto attacks. Which means that pressing W directly after landing an auto attack will make you do two attacks in very short time.
Also remeber a general farming tip: Don't spend more mana than then the gold you would earn for the minion kill.

Heal is excellent to stay durable and get out of tough situations that otherwise would have killed you.

Ignite is good for killing enemies slowly >:D

Flash is not needed because of Kassadins Riftwalk, but can make for nice plays. For example: riftwalk into enemy tower, get kill and flash out.

Exhaust is also strong. It makes your enemies easy targets >:D

1. Riftwalk (R) in think carefully if you can get out of there without dying.
2. If you went for a Deathfire Grasp, pop it now.
3. Null Sphere (Q) to deal damage and get your shield as fast as possible.
4. Force Pulse (E) to apply a slow that makes it easier for you to perform the next step in your combo.
5. Do a auto attack
6. Nether Blade (W) directly after the attack lands.
7. Ignite.
8. Do a slick escape with Riftwalk or pop Zhonya's Hourglass while the Ignite is ticking.

All in all we can easily say that the thing that Kassadin really needs is damage. Build pure AP and the items that you thinks suits the current situaton. There are many different items and you have to know them all to make sure that you build the perfect Kassadin for your playstyle.

Good Luck, Summoner!

//SOTH