The reason for me making this Attack Speed Kassadin Build is because I feel like the Normal Kassadin build is very bursty, and nukey but lacks that extra umph when your combo doesn't take down your enemies. Also there is a serious neglect for Kassadin's passive ability. 15% magic reduction and all of that resisted magic goes straight towards your attack speed. Since Kassadin is a Mid Lane Champ he will be facing another AP Champ 9/10 times so your attack speed will skyrocket so you can do massive amounts of damage quickly.

It's kind of self explanatory. If you aren't a lvl 20 or higher, don't waste your IP on runes, it's just not worth it with lower levels.

Ok, what I have done with this build is taken the "Excellence is Null" Kassadin Build (Which is an amazing guide to how to use Kassadin and I highly recommend reading it for all Kassadin users!) and I have replaced Lich Bane with Nashors Tooth. The reason I have done this is because Although Lich Bane does very well with Kassadin, because you aren't building your Attack Speed by the time you Void Walk into the fight, Auto-Attack, Null Sphere, Auto-Attack, etc. You're dead. There just isn't enough time to wait for your Auto-Attack. When you combine the massive attack speed from your passive and Nashors Tooth with your high AP from your Nether Blade Ability you can do some serious damage extremely quickly, If you combine this with Kassadins regular combo of Void Walk, Null Sphere, Nether Blade, and Force Pulse you're almost always guaranteed a kill! Also I realize that boots have become very popular and I understand why, but with an amazing ability like void walk, you will rarely need boots, if you find yourself being focused with a lot of CC I'd recommend taking it however, most of the time you won't need it since you have Void Walk on such a short cool down and with Seraph's Embrace you won't even need to worry about the lost manna from using it. Also If you find yourself in a situation where you are getting alot of kills sell an item if you have to and get mejai's soulstealer it will increase your AP like crazy with each kill.

Link to Excellence is Null