This build is under review since the recent change to Kassadin's "Nether Blade" skill.

This build is designed for using your auto-attack to damage champions, farm creep waves, and destroy turrets, whilst using your main skills to assist you to close the gap, escape, and deal some pretty decent burst magic damage whilst disabling your targets.

You will start out just as any Kassadin would, but with a bit more survivability given the runes and masteries that I would suggest. You will be playing as a slightly weaker shadow of Kassadin around levels 7 through 11, where you still have escapability and a lot of disables but can't nuke as hard or as often as any AP-based kassadin can. Finally, from that point onwards your attack speed and damage should be sufficient for you to keep up with the best on your team and annihilate the best on the enemy team.

To carry this build to mid-late game you will need a large amount of money, so you should only attempt this if you are efficient and practiced at farming creep waves early, mid, and late game. I might update the guide at a later stage to reflect what I know about farming effectively using Kassadin.

At the end of the game you will be able to crit over 900 with 60% crit chance. You will be able to attain at least 80 Armor penetration from Sword of the Divine's and Nether Blade's actives. optionally, you could add about 24 from runes, 6 from masteries, and quite a lot extra from items, putting it easily over 100.

Rather than max Kassadin's armour penetration through items like the Black Cleaver or Last Whisper I have opted for making him attack faster and crit more often. I think his natural armour penetration, along with Sword of the Divine, gives you enough armour penetration that you can focus your item build on other damage areas.

I recommend getting Sword of the Divine early to bolster Kassadin's shockingly slow attack speed. Phantom Dancer & Infinity Edge follow to add crit chance and a bit more attack speed, as well as the 250% crit damage. Finally I've put in the Bloodthirster to stack some damage and life steal to sustain the barrage of damage.

I have also included Banshee's veil in this build for 1 simple reason: I only seem to die if I can be successfully stunned or disabled and cant Riftwalk out. This item should give you more grace to be able to come and go as you please and avoid those unfortunate CC-based deaths.

I have also had success with Wriggle's Lantern since the blue and red buff are both beneficial to this build. That is why I use 1 point in Utility Mastery whether or not I decide to buy this item. Wriggles can have 2 other major uses:

• To destroy creep waves if you are being pushed have to deal with a lot of minions, this Kassadin build can effectively defend against Super Minion Waves. It also gives the survivability afforded by life steal.
• To place the ward in places where others on your team can't easily get in and out of. This can synergise with teams that use teleport or other global moves for pushing or backdooring strategy.

I like Ninja Tabi because Kassadin is likely to take a lot of auto-attacks from enemies who arent sure what to do with him. They are cheap, and the mastery towards dodge chance is low on the tree. I have also used berserker greaves when I feel that I need to fast-track my attack speed to become more useful as a melee fighter earlier in the game (for example, if your team is without a decent ranged carry or AP nuke and you have to do the work yourself).

I would like to say that I am still testing Guinsoo's Rageblade, the Hextech Gunblade, and Banshee's Veil to see how these items change the dynamic of this build. For now I have chosen to go either Wriggle's or Banshee's because I understand those items well and have used them effectively on other champions.

Kassadin's passive is usually not noticed or used by Kassadin players as far as I have seen. Kassadin has a natural magic resist, and benefits from taking magic damage. He converts the magic damage into attack speed. You will see a little "Void Stone Empowered" icon when this is in effect. This skill can help you to destroy casters more effectively, or do more damage in team fights where you are affected by ranged or AoE skills mid-fight. This will afford you survivability and a slight buff to your attack speed which can make a difference in combat.

Kassadin's Nether Blade will synergize directly with this strategy, giving you a large amount of armor penetration. Taking relatively early skill points in the nether blade gives a more powerful mana regain from its passive and a bit more armor penetration early to demolish enemies. The mana regain is crucial in a build that does not cater for Kassadin's endless thirst for mana.

I have learned that early on the Force Pulse can be a huge surprise damage dealer, since you typically add a level to it before it gets used again if you focus on that skill. Since our early-game Kassadin is not going to be doing that much melee damage just yet, I try to add 3 or 4 points to force pulse before switching the focus to Nether Blade.

From a gamplay point of view, his slow (Force Pulse) and blink (Riftwalk) abilities are very useful, and synergize well with an AD-Based Kassadin strategy in 2 ways:

• Chasing and disabling an enemy in order to get the kill: Kassadin's slow is 50% (HUGE compared to rylai's sceptre and some other slows in the game), and the Riftwalk ability is essentially spammable if you have the mana, and deals damage to boot.
  
• Running away from enemies, either by slowing them or riftwalking away. Slowing them in this scenario can save friends too rather than simply leaving them for dead.

As for the silence skill, Null sphere, you'll notice that I cbhoose it at level 1 and not after that until the other skills are maxxed. The reason I do so is for level 1 safety (silencing moves like fiddlesticks drain, etc), harrassment (since if they are silenced they usually cant retalliate with their own skills), and, in early game, hitting those hard-to-hit minions to increase your bank size.

Null Sphere levels up with quite a decent amount of damage and a longer silence duration which can both be very useful. Despite this, I prefer to get my damage as AoE from the Force Pulse in early game because it is effective in more situations. Silence only works on skill-casters but slow can effectively disable melees like yourself too.

For Null Sphere, the play style that I would recommend is not to try and use silence to disable a target for attack, but instead use it defensively. For example, if the tables quickly turn on you, an enemy comes out of nowhere, or you see someone channelling a move on you or an ally, you may be able to use this skill to disrupt their skills and ruin their plans. This type of usage would not require more than 1 level in the skill early on.

The runes I currently use for playing this build are the same as Stonewall008's Trundle Jungle runes.

Flat CDR Glyphs are my personal favourite, and armour Seals are a basic need for melee champions in my opinion.

They aren't the best choice for Quintessences and marks, where I would probably replace flat attack damage with flat Armour Penetration to synergise with the Nether Blade and cause more late game damage than flat damage runes can provide
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Since I haven't bought and tested the armour penetration runes yet, I thought I would show the ones I have tried and tested to play this build successfully even though they aren't perfect.

As any good build guide will tell you, these are preference-based.

I believe in exhaust for extra melee prowess especially early and mid game, and Clarity to help with mana problems all game long. Since they conveniently placed on the tree, I choose the mastery for each.

Other good options are:

Flash:
I love a good extra flash on Kassadin, scares the newbs when they think they know what you can and can't do.

Ignite:
Could be a good choice for extra burst damage and could add the 10AP mastery if you like your AP cheap.

Teleport:
He's so mobile I feel this is a waste on him, but if you really like it it could be deadly too.

Anything else:
It's up to you! I wouldn't even vote down a heal if that is the way you play. Keep it simple and know what you're doing is my advice with summoner spells. Don't outsmart yourself.

I like to keep my masteries balanced and so I havent maxxed out any 1 area in this build.

Offense:

Crit chance, attack speed, and armour penetration! 3 things that you need to use to make it work. This is an obvious choice in my opinion. As mentioned in summoner spells you might like to add the ignite mastery, or change the exhaust mastery for another if you don't want to use exhaust.

Defense:
A bit of armour is always good for a melee-based champ, and I am currently using dodge chance boots so i like that mastery. The problem with it is that if you find in early game you are stuck buying Berserker Greaves to try and carry your team, these mastery points go to waste. Another option would be to put the defense points deeper into the Utility tree, reducing defense to just the MR and Armour masteries.

Utility:
I live by the Awareness mastery because outlevelling your opponent can be a massive boost and is definitely required in solo lane, where you might end up.

As mentioned before, clarity mastery is taken because it is in reach and it is helpful to the team. If you have this mastery, you should have an eye out for people with no mana and replenish them where applicable. This can also be used to replenish your whole team if they are close together.

I previously mentioned I like to get the blue buff to sustain Riftwalk after I have enough attack speed to kill the jungle creeps efficiently. I also use the red buff to apply slowing to my attacks and assist in the already unbeatable chasing power of this build. It is for these reasons that I chose to put the final point into utility mastery.

If you chose not to use dodge chance in Defense, I would probably put the 3-4 extra points into Utility Mastery and Meditation.

Pros

• Cheap armour penetration
• High mobility and escapability
• Strong disables including AoE slow
• Mix of magical and physical damage

Cons

• Mana problems all game long
• Lots of gold required
• Low defense: susceptible to players with high AD or AP burst if you are not able to Riftwalk away
• Can be dominated in lane by ranged AD and ranged casters if you're not careful