4/10/17: Runes have been changed slightly AD from Lithality. And AA build changed to fit meta.

11/8/2017: Runes updated to patch 7.22

If you are looking for a bully in lane, character who easily roams, and someone who can dominate teamfights and or assassinate people, Kennen is your rodent.

Pros:
Very Mobile
Bully early game
God lategame
easy to farm with
no mana

Cons:
If caught out Very squishy early game
can be boring to play

Most people believe you should pick Q,W, then E for level 1,2 and 3 then max R>Q>W>E
I also believe you should pick Q,W, then E for levels 1, 2 and 3 in that order. But I prioritize R>W>Q>E. Your Q has the highest possible damage output which is why people usually want that skill maxed first but it has an actual lower damage output than W. This can be explained fairly easily by chance on hit. W is a guaranteed hit you get 1 stack of Mark of the Storm from W's passive and you have a 100% chance of hit with W's active. Q on the other hand is a skill shot that hits the first thing that comes in the way. So if the opponent is smart he will always be behind minions. If you are to rank up Q first you overall damage will actually be lower in lane than if you max out W first. Plus leveling up your W first also increases your W's Passive damage starting at 40% of your ap for bonus damage to 80%

For every build but AA's build has a similar core item list Sorcerers Boots, Protobelt-01, Zhonya's, and Abyssals. I Value Abyssal as the first or third item you should buy. First if you are against an AP top like Akali,and third against everyone else. Hextech Protobelt-01 is the normal first buy because it's such a bully item inlane and makes your end much more forgiving for going in with the lifesteal. Zhonya's is a must buy second or first. If your not being bullied Protobelt is the better buy. Even if your not being bullied at all Zhonyas is such a strong item on you for team fights it's a must buy every game.

Void Staff is the best last item you can build if you're not going offtank

Rabadon's Deathcap and Rylai's are up in the air for what your team needs. If you need the off tank; Rylai's is the better option. If you think you can carry Deathcap is the way to go. Personally I love Ludens as a last buy but it just doesn't scale as well.


As for the AA build...I originally made this for fun to joke around. But a real AA based Kennen has appeared so I fixed the build to the meta.

Passive: Mark of the Storm
Kennen's abilities add one stack of Mark of the Storm to their target for 6 seconds. If the target reaches 3 stacks, it is stunned for 1.25 seconds and Kennen gains 25 Energy.

Q: Thundering Shuriken
Cost: 60/55/50/45/40 Energy
Range: 950
Kennen throws a fast moving shuriken towards a location, causing damage and adding a Mark of the Storm to any opponent that it hits.
Throws a shuriken that deals 75/115/155/195/235 (+75% Ability Power) magic damage to the first enemy it hits.

W:Electrical Surge
Cost: 40 Energy
Range: 725
Kennen passively deals extra damage and adds a Mark of the Storm to his target every few attacks, and he can activate this ability to damage and add another Mark of the Storm to targets who are already marked.
Passive: Every 5 attacks, Kennen deals bonus magic damage equal to 40/50/60/70/80% of his attack damage and adds a Mark of the Storm to his target.
Active: Sends a surge of electricity through all nearby enemies affected by Mark of the Storm or Slicing Maelstrom, dealing 65/95/125/155/185 (+55% Ability Power) magic damage.

E: Lightning Rush
Cost: 100/95/90/85/80 Energy
Range: 200
Kennen morphs into a lightning form, enabling him to pass through units. Each enemy unit he touches takes damage and receives a Mark of the Storm.
Kennen doubles his base movement speed and ignores unit collision for 2 seconds, dealing 85/125/165/205/245 (+60% Ability Power) magic damage to any enemy he passes through. Additionally, Kennen will gain 10/20/30/40/50 Armor and Magic Resist for 4 seconds.Kennen gains 40 Energy the first time he passes through an enemy.Lightning Rush deals half damage to minions.

R: Slicing Maelstrom
Cost: No Cost
Range: 550
Kennen summons a storm that strikes at nearby enemy champions for magical damage.
Summons a magical storm for 3 seconds that deals 80/145/210 (+40% Ability Power) magic damage to all enemies near Kennen every 0.5 seconds. Each hit applies Mark of the Storm, up to a maximum of 3.Each time an enemy is struck, further hits deal 25% less damage (minimum of 50% damage).

In lane your Skill Sequence for harass should be:
W's passive to harass when the opponent comes in to hit a minion.
cast W if they are stupid enough to try to hit more minions while they have Mark of the Storm on them
Q them when you can get a guaranteed free shot on them. Holding this ability gives you more control in the lane then using it on cooldown.
Use your e to run away from possible ganks or get your third Mark of the Storm if you are getting help from the jungle to get a kill and or you can kill them with your ulti.


In team fights if are with your group poke with your Q. Your AA is no longer as strong in this poke section because of your short 550 ranged. Ideally you will want to be flanking the other team from the rear dashing in with your E and popping your R when you have 3-5 members in your ultimate leaving your team to follow up and get free kills.

In ranked play you should be a bully during the laning phase. You do not have the best all in, but you are extremely good potential to deny farm. Playing safe and keeping them off your farm with your passive W and your W will ensure a solid gold lead. When you have a ganking jungle on your side having your stun and or your ulti almost guarantees a kill. Late game I play Kennen as a flanker or an assassin. I will wait behind enemy lines to try to pull off a 3-4 person stun with my ultimate allowing my team to be victorious. That being said if I catch an ADC or a high priority target out of position and I have ultimate I won't hesitate to use it on one person.

Kennen has a easy time farming with your W's passive you can both AA creeps and use Q. Your W's passive is a more reliable source of harass so if you need to use your Q to farm it is not a terrible thing. But as any player denying farm is just as important as farming yourself. Kennen is god at denying farm. Push the lane in early so the tower eats some of the farm. about 2:30 minutes in you should be warded and be expecting a gank but you should be level 3 and have your E. the goal is over 100 cs at 15 minute mark, and them to have below 80 cs.

So for the new preseason I have chosen Domination>Sorcery for his AP build. He scales well more with burst over poking. The first choice, Electrocute was the main cause for me to pick it first. Second is The cheap shot. Since your main goal is to enter a fight push R and stun them and do lots of damage it fits in well here. Ghost Poro is my choice for third pick because I like to roam. Ingenious Hunter was chosen because CDR is king for Kennen. In sorcery i chose The Ultimate Hat as your Ulti as an AP is king. More its up the better. Lastly is Transcendence. Because he naturally picks up max CDR going over cap is no longer as much of an issue since it becomes adaptive AP or AD. I picked this over Inspiration being secondary because the Hexflash while cool feels underwhelming with the 2s cast timer. Protobelt is still better than going to another tree.

Liandry's not strong as I thought
Protobelt while not my favorite first pick is still the best first buy
we will see what happens with Rylai's with the new expansion

Luden's was a priority before Hat originally on my in my guide, and while it is the more fun item it is less efficient when you're deciding to buy it you need the extra 35% ap over movement speed. I was using it as a third item to roam 20-22 minutes in for the longer laning phasing games what happens more often than not in low elo games. But with Protobelt-01 being stronger than I hoped that is no longer a feasible.