hey there got some points you could improve

1. Magic Pen Discussion - Credit to Indignant Soul
Maybe a little bit to long but if you don't wanna read it you could just skip it.
And what's written in there is quite useful but you should try to shorten it.
2. You got some walls of text :P try to get rid of them by using pictures

Moreover I like the layout of your guide, with the linedivider's and the texts which are left and right most of the time.
all in all a great job +1

Keep on going like this Rys you are great ! :) ^^

Such a great guide!!!!!!!!!!!!

when u change the build Please put a change log in and Why u changed it , Taken my vote way till thats fixed

Found a few mistakes in your guide. Here they are:

0 MPen (Let's assume she went with Mercury Treads)
No auras
SPACE Ashe will have:
23% magic defense
1307 hp to get rid of

I ASSUME THAT "SPACE" SHOULDN'T BE THERE, FIX IT! =D

I'd like to point our that if you are going to do math based on these AP ratios Ahri is apparently a really low damage champion. Instead use the real ap ratios? Calculate an abilitie's AP ratio by total damage it contributes to the ability not to one part of it.
Assuming you can hit with evrything this champ has relativeley normal AP ratios.

this was probably supposed to be bolded that wasn't in your guide, so fix that too!

I can tell you obviously put a LOT of effort to this guide. There are probably more errors in your build (im going to guess you're tired after this) and you definitely deserve this +1 im going to give you. I'm even going to +Rep you as you definitely understand Ahri. Great guide, fix these errors, and keep up the great work! =D

Now if only I finished my Xerath build, 40% complete atm =P I guess i gotta work harder too! XD

Great Guide :). Although I personally didn't need it since I was already basically doing essentially everything mentioned in this guide without reading it. Although normally For the summoner spells I go with flash and clarity cause clarity helps me with early game mana problems and emergency's, and with the items I usually get Morello's evil tome instead of Deathfire Grasp, I usually keep Rylai's Crystal Scepter and dont buy Zhonya's Hourglass and buy the time I buy all that I usually don't have enough gold to buy anything else or I just plain forget to go back to buy, but that doesn't matter.
Great guide never the less :D

Great guide!
I have been playing almost 100% with Ahri sins she came out, and have tried a few variations, it now feels like the last few pieces fell in place :P
my best is 14 wins with +1 K/D ration streak, I generally start off with doran's, boots, sheen and then pretty much follows this build :P

Good job!
Cheers!

Amazing guide ! Went 7-2-6 for my 2nd game with Ahri. I was really impressed with how much dmg Sheen (didnt have time to build it into LichBane, enemy team surrendered) did with her.

I cant get my 2 images together tho so I probably won't post it unless you want to see all my games :/

Great guide! I had mana problems the entire game without catalyst(RoA). But Golem buff solved them. And my 1st game with your guide i went 14/0/9 and one triple and one quadra kill. Thank you.
Here is my game:

I worked on MPen and Magic Resist Reduction efficiency on Ahri's skill.
I've put it on my guide if you want to see it. (As I don't want to put any advertisement on your guide's comments, I don't link it.)
I created an Excel sheet for the calculations. Ask me by MP if you want it. =)

You might want to do less harrassing with your skills (especially your Q).
A good tactics is to build stacks at your passive, and then just last-hit with autoattacks, letting the enemy push. Ahri shines when your jungler comes to gank your lane, so just be patient.

I like this build, and i love the will of the ancients giving me lots of sustainability in lane, the only problem is the mana problems early game if we dont have a jungler to give me blue buff