Greetings Summoner!

This is my guide to
So if you're planning to buy an good Ap mid / Jungle, Diana is the right one!
She's a pretty offensive champ on late game even on early she can harass people pretty easy.
She's pretty hard to lane against since she is completely unstoppable if well played.
I bough that champ some months after her release and I've been playing with her since so.
As well on this guide I'll teach you how to play as Diana on Midlane, I don't really like playing jungle to be honest but you can also use this guide to play her on jungle.

Alright for the runes I'm actually using
3 Greater Quintessence of Ability Power
9 Seal of Armor
9 Mark of Magic Penetration
9 Glyph of Magic Resist

With these runes you'll get 15 AP at lvl 1 and an good defense/magic resist rate.
For me they're pretty good and works perfectly on early game and on late game for that extra defense.
But you can also use her full AP rune page that's
3 Greater Quintessence of Ability Power
9 Seal of Ability Power
9 Glyph of Ability Power
9 Mark of Magic Penetration
It will grant you a good ap rate/early game dmg but you'll be a little weak against enemy champion attacks.

Her masteries are basically 21/9/0,
I'm using that basically cause she's really offensive since she's an assassin, at least that's the way I play her.
The Executioner will increase the possibility of getting kills when the enemy is on low hp and also The AP masteries will give an good ap rate.
The 9 on defense ,will get you an good defense rate and HP.
Utility masteries are mostly for supports and champs who doesn't really needs to deal some dmg.
Again, Diana is a Single burst champion that really needs to instakill some champions, you know that feel when you're playing Ashe and suddenly Diana gets over you Q'ing all the way and you don't know what to do?
Yeah, that's assassin Diana.

Diana has many builds but I'll teach ya'll her assassin build, that is the point of this guide.

As first time leaving the base, I'd strongly recommend you to buy Dorans Ring and two potions of your preference or wards.
At lvl 6, try asking for your jungler to hold the lane while you go B or if your enemy is on low hp try killing him.
If you go B buy another doran and potions so you can gank enemy lanes and go back to your lane if you fail ganking.
Small reminder, the build always change, so i cannot tell you exactly what items to get because as you may know league of legends is a dynamic game that plays against really tons of enemy compositions and champions, but as i said I'll tell you two builds that are almost always used and that do pretty good against most of enemy compositions.
1st Build
Rabadon's Deathcap
This is the core item for almost all AP Bruisers it will GREATLY increase your Ability Power getting you'r skills a lot of damage.
Void Staff
I like building this first because it's absolutely OP and since Diana's AP rates are OK it's really good to start off with some magic.pen and ganking enemy top lane and you also get some AP.
Lichbane
This item does pretty well since we're playing her as assassin and with this build Diana will be a single burst champion but if you build Lichbane you'll be able to deal some extra damage.
Abyssal Mask
this item it's basically like Void Staff but it ignores magic resistance instead of penetrating it.
Zhonya's Hourglass
This is an good item if well used, you can absolutely crush enemy combos cause of it's invulnerability and it'll grant you some armor.
Sorcerer's Shoes
This is the best for her cause as I told ya'll, we're playing her as an single burst assassin.

Crescent Strike
It's her core skill with it you can ult on enemy troops or champions without cooldown.
It has an good cooldown and damage, it has an own skillshot design it makes an smooth curve and at it's end you'll do AoE damage. So keep in mind to hit people with that part of the skill cause it'll be easier to hit them but when you go pro you can try to hit them with the curve,it goes trough minions and walls so use it to harass at lane phase.
This is how i'm used to use her Q, I always go to opposite side to my enemy and then I use it I don't really know if this is the best way to hit but for me it's the best way to hit enemies.

Pale Cascade
Make sure to just go on your opponent when this skill isn't on cooldown because this skill is perfect for her basically it gives you an shield and 3 orbs that deal damage on contact.
She creates 3 balls that deals damage to anything they hit and when the 3 balls explode the shield goes fully restored or overstack(IF you explode the 3 balls before the shield goes fully damaged you will get the same shield ammount and it will stack).
Moonfall
This skill is a crowd controll,
This skill does pretty good cause you can cancel enemy escapes and drag them close to Diana and also adding an slow effect.
As an example, you can cancel and jumps if you can match the time that ziggs or tristana jumps with your E, it'll cancel they'r jump and drag them to you cancelling they'r skill and also slowing them.
It doesn't do damage but it's the perfect CC for chasing/escaping.
Here, Have some examples of how using your Moonfall.
Play Video Play Video /league-of-legends/ability/lunar-rush-518

Pros
-High DMG
-Hard to escape from
-High max HP
-Hard to counter
-Good for ganking lanes
-Tons of aoe
Cons
-Doesn't like much CC
-Single Burst
-Medium Cooldowns
-Weak at Early Game
-Doesn't do well without items

This is the most hard champion you'll lane against he's WAY too hard since he has too many cc's including a silence and true damage meaning that you can't get close of him for too long, and if Cho matchs his Silence with your ult, he will cancel your ult and you will lose your combo.
Hard

This will be a pretty annoying match cause of his mobility, but you also have mobility so don't be too shy after lvl 6 you go on and crush with him.
Medium

This will be a pretty easy match they all say "omg akali omg omg" tell them "OMG DIANA" if you read this guide you'll for sure know how to beat her.
Easy

this will be a hard match as always try to harass him and then go for the kill.
Medium

this will be a medium match,try to flash after her and release your Crescent Strike,this is what i call "offensive flash" it'll force her to ult after you recover go on her and get the kill.
Medium

She wins the lane if you don't do well,she can easily counter Diana cause she has a lot of aoe and can harass Diana as much as Diana can harass her.
Medium

Make sure to miss her snared then when she uses it and miss you go for her she'll be forced to run,Diana can counter her easy as cake.
Easy

He can silence you and become invisible but that's not big deal i'd classify as a medium match.
Medium

you'll probably lose the lane since she doesn't really react against harass play safe till lvl 6 and then kill him just make sure to dodge his rockets cause it deals a lot of damage.
Medium

Pretty easy annie has a high dmg so does Diana Try going for her after she use her Q to farm and when she's witouth her stun.
Easy

This will probably be the most easy guy you'll beat on midlane since he's too weak for you try to harass him till lvl 6 and then kill him use your Moonfall if he try to ult because it'll cancel his ult.
Easy

Easy she's pretty annoying but if you get close of her she'll have to run for her plants i'm pretty sure she won't have time to do it.
Easy

This will get you in trouble since you can't just harass him because of his shield so watch it let he harass himself you'll probably will have to gank other lanes to get kills so try doing it since Mordekaiser uses HP on his skills let he hurt himself without getting you in trouble.
Medium

Oh yes,Anivia,NEVER,NEVER,Never dive her,only if her passive is off,but I recommend not to dive her so try harassing her and going for the kill when she's on half hp.
Easy

This will be an equal match because both champions have a good damage and high harass rate but he'll win if you just jump on him like a crazy brainless so try to using flash when he uses his Q when you flash also make sure to fight far away from your minions because of his ult.
Medium

Veigar is pretty easy to lane against,flash when he uses his stun,but NEVER stop on his front,try to always move,also don't let him farm much also his ult has an way too good damage you'll be forced to recall if you're on half hp.
Easy
you can also rush Zhonya's Hourglass and use it when he use his ult when he does you'll se an purple ball coming over you since it's an projectile you'll be able to dodge it with your Zhonya's Hourglass

Go4Him! consume his ult and when he's "ultless" you've gotta finish him as fast as you can cause if he uses his slow/speed buff you're not gonna get him easy.
Easy

she's pretty easy just dodge her Q then go for her if she uses her charm you still can get a kill but remember don't dive her if she has her ult.
Easy

this is pretty easy make sure to have your E when you go for her use it when she ults because it'll cancel her ult and she won't have that damage.
Easy

This you have uh 90% of chance of defeat so try to get your jungler to gank mid also don't waste your flash to reach him hold it for when you get the kill also fight far from the turrets if possible they're small but they do a lot of dmg,yordle stile!
Hard

She's pretty weak on midlane,just be carefull for her Rapel and stun,try not to dive her when she have these skills,also don't come close to her with too low hp her spider Q will kill you so try to not build much hp as much hp you have as much dmg she'll have.
Medium
Le Blanc
she has an good damage and also an great kit and long cooldowns try to take advantage of her cooldowns also watch out for who's the real Le Blanc.
Easy

QQQQQQQQQ on her,dodge her Q's and be smart,if you've read the guide,you'll know her weak points and the strong points.
Equal

Well Diana's Passive Moonsilver Blade scales pretty good for farming also i'll post an video about how to farm with her here soon, but by now, try just last hit the minions, and when you get the passive's 3rd hit try hitting your enemy.
Just don't advance your lane too much because if you do you might get ganked.

Offensive Flash, that's the word.
Some midlaners are just slow, take advantage of it, try running from them for a while and then Flash+ Crescent Strike and then finish him off with your combo.
Then you might think; "But why should i flash if he can simply skillshot me?"
A: If your burst damage is doing good, you will be able to finish enemies with one burst, and if you flash your enemy will probably think "Well she's gonna run" but you're not.
So when you flash off your enemy and combo him, If you combo really fast he won't be able to do anything and You'll probably kill him.

this was my guide about
She's my favorite champion and I love playing with ^^
hope you all enjoy it and have fun on fields of justice :D
Soon i'll be updating videos about how Farm, Using her Q, E, Passive and ganking.
Thank you all <3
Also i'd like to share, this is my first guide and you might see some mistakes such and english typos, feel free to hate and don't forget to upvote it so i can improve ^^