This is my take on playing Kennen. Other Kennen players might notice it bears some similarities to the "Kennen Hiiiyyahhhh" Build by Hugenjpana. Well, that's because I used his build when I first started playing Kennen. However, with the new masteries and my own opinions born from playing several games as Kennen, I feel that he is due for a few tweaks. Fun fact: the passive from Electric Surge will make every shuriken do bonus damage to a turret as long as you have it at 5 stacks when you attack the turret.

Pros:

• Very powerful burst damage.
• Nice crowd control
• Excellent farm
• Great at saving teammates
• Very nice harass
• Can stun multiple targets at once
• Difficult to catch

Cons:

• Tends to get focused
• CCs like stuns, snares, and popups are major destroyers to Kennen. (Slows not as much)
• His skills have a longer than ideal cooldown if he doesn't have cooldown reduction
• Due to said cooldowns he does tend to get K/Sed, or at least I do.
• Pretty squishy

I like 9/21/0 since defense makes him less squishy and items will give him the damage he needs to shine. It's very possible that he would do some nice damage with a 21/9/0 setup or even a 21/0/9 setup but I think he would be too squishy to be in a typical 5v5 teamfight (I/E: getting focused like crazy).

Love It:

Ghost: This bad boy will get you out of most surprise ganks as long as you don't get CC'd too hard. If you play aggressively, this is also a nice spell to use to get into the mix quickly.

Flash: This is a useful spell for getting Kennen out of those AOE CC's and other scary attacks. It is also very, very, VERY nice for getting in the middle of an enemy team to pop off your ult and then Zhonya's.

Cleanse: This is a very nice little tool to get out of those CC's that just destroy Kennen. From my experience, if Kennen can't move like he needs to, he's about to die. Between maneuvering for Thundering Shuriken and hitting enemies/avoiding attacks with Lightning Rush he NEEDS to keep moving.


Meh Spells:

Ignite: This spell rarely is ever bad on most champions but it's not fantastic on Kennen. The extra damage is alright but if there are other people on the team with Ignite you can just ignore this.

Exhaust: Another ok but not great choice for Kennen. Because Kennen has his stuns the slow isn't really needed but it's a good way to stay alive against AD carries.

The list of items at the top is pretty typical for me but there are some other items I may take depending on the situation.

Core Build:

Sorcerer's Shoes: This pair of shoes here is very nice to have once you've finished Will of the Ancients because you're sitting around a comfortable early/mid 110-ish AP and you should be able to harass and solo most of the people on their team.

Will of the Ancients: This thing is just so wonderful for Kennen and I cannot stress that enough. With 80AP and 25% Spell Vamp you'll be able to hang in your lane very easily. Running on Energy with Spell Vamp is very powerful and late game Kennen can get an easy 200+ Health gain after every ability. If you don't NEED boots of speed, fudge them to rush Will of the Ancients ASAP. You can handle most movement situations with Kennen's Lightning Rush.

Rabadon's Deathcap This beauty should go without saying. I could mix poetry about how nice it is to destroy the enemies with massive nuke damage thanks to this item but if you've seen one AP champ with this item you should already have a pretty good idea what this thing does.


Situational Stuff

Rylai's Crystal Scepter: The only reason I don't main this item is because Kennen can stun with any of his abilities. HOWEVER, if the AD on the enemy team sucks or is nonexistent than this is a pretty decent item to have in place of Zhonya's Hourglass. (Despite the nice combo with Zhonya's and Kennen's Ult it isn't actually needed to play a successful Kennen)

It you find the enemy's AD is just too much for you, get Zhonya's in place of Deathfire Grasp and if the enemy is STILL too damaging get a Rylai's Crystal Scepter after Rabadon's Deathcap or before if things are getting really bad.

If the enemy is stacking too much AP for you to deal with I'd recommend moving Deathfire Grasp until after Rabadon's Deathcap and getting a Force of Nature or Abyssal Mask in place of Deathfire Grasp. Getting Magic Resist with Abyssal Scepter or Armor with Zhonya's Hourglass early can help you survive more attacks but I don't think you really need these items until late game (Especially since a lot of nasty AOE CC's are Magic Damage). Prior to Deathfire Grasp, I used Nashor's Tooth because the Attack Speed got more hits on his Electrical Surge's passive, the cooldown let him last hit more often with his Thundering Shuriken and hitting the enemy team more rapidly with his Electrical Surge. It's nice but Deathfire Grasp is cheaper and it's Activated Ability is very dirty when you've got a Rabadon's Deathcap with it to make the enemy take rediculous amounts of damage before you even use one of Kennen's actual abilities. You should initiate with Deathfire though since it does damage based off the target's current health, not maximum health.

I wouldn't advise it, but sometimes you have to get Mercury Treads instead of Sorcerer's Shoes. Hopefully you can decide between the two boots before you've finished Will of the Ancients.

Why Nashor's Tooth? I personally like it because the attack speed allows him to get more hits with his Electrical Surge's passive, the CDR allows him to spam his Thundering Shuriken more and this prevents him from getting K/S'd as much. The ability power is nice because.... he's an AP character so... Yeah. Unfortunately the mana regen part of the weapon is completely useless on him which is the only reason I'd consider not using Nashor's Tooth for an item like Rylai's Crystal Scepter or an early game Zhonya's Hourglass.

Kennen is a very good mid or solo champion but I think he's also equally amazing at duo laning.

Mid: Going mid as Kennen is pretty easy against most champions but there are a few Champions I personally don't like to go against. Caitlyn, Morgana, and Ryze are the big three that bother me but Swain is also annoying. Caitlyn will be able to out-range you, disrupt your movement with traps, and stay behind minions the entire time. Honestly I'd switch with somebody else immediately against her. Morgana and Swain aren't too bad to deal with but you should rush Mercury Treads or Sorcerer's Shoes instead of a quick Will of the Ancients. As long as you can dodge their snares you should be fine. Ryze is a huge problem for me because he has a target snare. I don't see a lot of Ryze players, and even less that go mid, but the ones the I have mid against become quite a hassle to deal with because of the snare. The only one of these champions that I find Kennen just can't handle is Caitlyn. Harass with Thundering Shuriken and Electrical Surge. At level 3 Kennen becomes a monster with his abilities and can beat most champions in a DPS battle. By initiating with Lightning Rush, stacking a second Mark of the Storm with either Thundering Shuriken or Electrical Surge, and then stunning them with the the skill you did not use for the second mark. This probably won't kill the enemy since you aren't an atom bomb yet, but they will definitely be scared of you (unless you're dealing with those players who use Heal).

Solo: This applies to solo'ing against two champions. Solo'ing one champion is played mostly just like playing mid. Kennen is pretty good in a 1v2 lane because his Lightning Rush let's him dodge the really powerful attacks and his Electrical Surge can harass both enemy champions at once. If you do find yourself in a 1v2 I would recommend switching the order you level your Thundering Shuriken and Electrical Surge. Lightning Rush at and away from the enemies and then using Electrical Surge will work well enough to harass them until your jungler can come in and the two of you can destroy them with your stuns and the jungler's damage.

Kennen's role in teamfighting is crucial but it can be a bit difficult to tell exactly WHEN he should go all-out in the battle. If you have Lightning Rush, Slicing Maelstrom, Flash, and Zhonya's Hourglass then Kennen could easily initiate by rushing in, popping his ult and then immediately popping Zhonya's. Once Zhonya's is over you should Flash out of there IMMEDIATELY. Seriously. The enemy team will be just a tad pissed off at you at that point. You may even have to Ghost or Cleanse if their CC is really bad. (Although if they have hard CC you shouldn't be jumping in like this anyway)

Kennen is at his best in a teamfight when the fight is still early on and the enemy is still pretty grouped up. Hopefully your tank or tanky-dps is already in the fight and the enemy has blown some of their abilities already. This is when you Lightning Rush in and pop off Slicing Maelstrom. When a vast majority of the team has a Mark of the Storm on them it's time to use Electrical Surge and hit them hard for some nice multi-target damage. Thundering Shuriken has a low cooldown and this should be used for picking up kills or stunning a runner. Because Thundering Shuriken has a low cooldown when maxed, you need to spam this as often as you can to finish off the enemy team.

Kennen is a pretty fun nuke-AP-champion to play and I find this build useful in both 3v3s and 5v5s. I've saved more than a few of my allies with his stuns and his Shuriken skill rips through the enemy's health. As long as you can avoid CC you should do fine as Kennen. Also try to avoid running into the middle of a mob. You'd think that's common sense but I've seen plenty of kamikaze Kennen players run into the middle of the enemy team and ult like they think they're a god or something. (I've done this myself more than a few times and it really doesn't help the team much)