Akali is probably THE best anti-carry in the game, and can take out squishy ad-carries or squishy AP champions. I played Akali for many matches, and i tried to play her in every possible way. Akali is an AP carry/destroyer/assassin and a really good snowball hero. If you have a decent start you will for sure own the enemy team the whole game. This is basicly a guide on how to play akali against any encounter top or mid. (Please don't go other lanes with Akali since she's being kind off useless without levels)

Pros

Cons

-Hard to harass because of her Twilight Shroud

-Melee AP

-Can burst enemies extremely fast

-Got no CC

-Low cooldowns

-Easy to counter with a Vision Ward early game

-Good at escaping/chasing

-Requires very good judgement

Normally when i'm Akali, whether i'm top or mid, i'll go with Flash + Ignite


Flash
Flash is really good for akali since it can often give her the last bit of range needed to use her ultimate Shadow Dance flash is a must since it's a great escape mechanism, and a great way to hunt your enemies.


Ignite
Normally ignite is my secondary summoner spell since it gives a good finisher when ganking a hero early game, and after it's used you will get 5 more ability power, and 5 more attack damage because of the mastery Summoner's Wrath


Teleport
I often change ignite with teleport, since it's a very effective way to get to other lanes, and help them out. You can often surprise your enemies since it's hard for your opponent to call "miss"


Exhaust
exhaust is extremely usefull, especially before you get Rylai's Crystal Scepter or Hextech Gunblade It's also very usefull to counter a gank coming from the jungle, and escaping some situations.

Akali's abilities:


Mark of the Assassin (Q)
Mark of the assassin should always be picked in lvl 1, since it's good at both harassing and farming depending on who you're laning against. It's very good for lasthitting, since you can throw it, and auto-attack right after taking atleast half the minions hp


Twilight Shroud (W)
Twilight shroud is extremely good for farming + harassing. I almost pick this every time when i hit lvl 2, since it's good to avoid being harassed and great for farming. Also it's a great tool to prevent being ganked by their jungler, since it both makes you invisble, but also slows enemies.
But beware! you're not always in safety just because you're in shroud. Often enemies will have a pink ward, and alot of spells will reveal you
Lee Sin will reveal you with all of his abilities, and they're doing AOE dmg, so it's almost impossible to avoid. Lee sin is your worst enemy!!!
Twisted Fate will often be seen mid, and his ultimate Destiny will reveal you for 6 seconds when he's lvl 6-10, which is more than enough time to kill you, or atleast make your shroud go away.
Nidalee you will also meet this champion mid, and she can reveal you with her Bushwhack even though you should be able to avoid it, it happens you step on it
The are more abilities that reveals you, so know your enemy!!


Crescent Slash (E)
Crescent slash is a great ability for lasthitting multiple minions. This ability is very usefull when at a tower since early game since it will damage both melee and ranged minions to hp where they can take 1 or 2 turret attacks without dying (changing whether it's a melee og ranged minion)
Also this ability got low cooldown, and it CAN be used to consume your mark from Mark of the Assassin


Shadow Dance (R)
Shadow dash is a really powerfull ability with a high range, which allows akali to escape and hunt extremely succesfully. there can be up to 3 stacks on this ability (generating over time), with only 2 seconds cooldown in the begging, and 1 second when you hit lvl 16. Whenever Akali gets an assist or kill (Doesn't matter if she even used this ability) she will immediatly refresh 1 stack.

this is the sequence i normally go with:

Ability combo with Akali:

early combo:
(Q) --> (E)
This combo should be used from lvl 3, and then at every possible moment in your laning phase. You should always (atleast very often) have mark (Q) applied to your enemy, and if he tries to get close, just press E (crescent slash) immediatly to harass him/her good.

lvl 6 harass combo:
(Q) --> (R) --> (E) --> (R)
You can decide yourself if you want to use the last shadow dance (R), but it's for getting away, if you're against a hero who can harass you after you used your combo (just target his minions if they're nearby, else use Twilight Shroud (W))

lvl 6+ 1v1 gank:
(Q) --> (R) --> (E) --> (Q) --> Auto attack --> --> (R)

First you mark your enemy, and wait for cooldown to go off (Mark lasts longer than cooldown) When cooldown goes off, you follow the combo step by step
In the end you can use shadow dance (R) again if needed and ready, or use it to get away in case you tower dive (which is do-able on Akali)
If you're against a champion mid like zyra, lux or annie make sure that you either avoid their snare/stun Light Binding Grasping Roots or try to bait it BEFORE you go. In case of annie you should click her, and check if her next ability will stun (because of her passive) Pyromania

Combo for when you got Hextech Gunblade:
(Q) --> (R) --> (E) --> --> (Q) --> Auto attack --> (R) --> --> Whatever you have ready ;)

You should just use this combo instead of the one above when you own a Hextech Gunblade

In all these combo's remember to proc the first mark (Q) with crescent slash (E) and the next one with auto attack so you'll have crescent slash ready soon again.

Items to buy level 1

x9
sight ward x2
This is my buy level 1 with akali in 80% of my games. Sustain with Akali is EXTREMLY important, since level's is much needed. The wards of sight is very important to prevent getting ganked, and when you're mid, you should place 1 ward in the top bush when you're lvl 2 or 3, and when it runs out, place the next ward at the same spot. When playing top you should place it in the bush right under the lane, in the river where their mid can come from. I illustrated it here:To see the image right click the icon --> Open image in new tab (sorry for this guys)
The red circles are where you should ward when playing mid akali (Only 1 place at a time)
The green circles are where you should ward when playing top akali (still only 1 ward at a time)

Alternative items to buy level 1

Sometimes i buy different than the 9 healing pots. Then I go with:

x4
sight ward

I buy this if i feel i can get an easy first blood. It's generally when i'm against a melee champion, or a champion without a good escape mechanism. When you try to get the kill you don't have the potion on. You harass alot, and when they hit around 50-60% hp from your harassing you can try to go. Just do like you always do, but if your enemy tries to turn on you, wait untill you go to around 50-100 hp, and use the potion. Then you instantly have 200-250hp, which can be alot in the beginning. This has giving me firstblood alot of times, and you opponent often forget to look at your items, making them unprepared for the extra health.
Here's a video showing an example of how to use it: http://www.youtube.com/watch?v=DQ48Y1FxaAU&feature=youtu.be

First time you recall

Now it all depends on how much gold you have, and who you're facing

When having 0-400 gold:

Refill + sight ward and maybe get or depending on who you play against, and your gold.

When having 400-1000 gold:

I would always make sure i have atleast 1 sight ward and 5 whether you're top or mid.

When being mid:

+ and if i have enough gold

When being top:

+ and if i have the gold

When having 1000-2000 gold:

I would still make sure i have atleast 1 sight ward and 3-5 whether you're top or mid.

When being mid against high burst Annie for example:

+ + and/or

When being mid against consistent DPS Karthus for example:

+ + Make it if you have the gold

When being top against high burst Zed or Garen for example:

+ + and/or

When being top against consistent DPS Udyr for example:

+ + Make it if you have the gold


If you have more than 2000 gold just build towards the core items.

Core items

+ +

Hextech Gunblade Akali got no natural CC, so hextech gunblade is an extremely good slow, and it also provides AD+AP lifesteal+spellvamp, which makes her able to heal half her hp of just one creep wave, and also Akali can surprise enemies, and turning on champions with full health, even though Akali only got half. It's brilliant for sustain, and if you have a good early game you can get Hextech at 13 minutes, and start ganking all the other lanes with ease.

Rylai's Crystal Scepter Rylai's is a really good slow, which works very well on all of Akali's abilities, while also providing a good amount of health and AP. This item makes her able to chase, and even dive under towers easily because of the health gained.

Warmog's Armor I also consider warmog's as an item you should get in 90% of your games with Akali, since i think akali is a great tank, and needs this to be able to show her full potential. Giving Akali 1000hp more will not just give her 1000hp. It will increase Akali's EHP (effective health pool) by ALOT since she will be able to survive more, and thereby spellvamp/lifesteal much more hp from her hextech gunblade (Which is why you should have warmog's in 90% of your games)

Endgame items

In the end there's alot of different items to choose between.
I love getting Zhonya's Hourglass since it makes you able to jump in, kill the ADC, and then use the hourglass to wait for your team to react. You will most likely have warmogs + rylai's by now (It's lategame) so you'll have plenty of HP to survive this.


Abyssal Mask is also very effective when you're against AP heroes. Not only does it give you alot of magic resist + AP, you also get an aura which decreases your enemies magic resist, making it even easier for you to nuke them fast.

or
Rabadon's Deathcap or Guardian Angel
I know there's a big difference on these items, but as my last item i often buy one of these. It depends 100% on your enemy team, and if you're winning or not. If you can survive jumping in, and use hourglass you should go with deathcap, but if you can't, and you die all the time, you should go with guardian angel.

Alternatives:

Lich Bane is a very viable choice too since you're using abilities all the time, and still auto attacking all the time to proc the effect. I often go with this item when i have a really good game, and i can avoid dying too much.


Mejai's Soulstealer is a very good choice for early game, and as Akali you won't die much, and you'll be able to keep your stacks. When buying this item you will often reach 20 stacks, giving 180 AP and 15% cooldown reduction, which is just overpowered on Akali. Remember to buy tanky if buying Mejai's Soulstealer


Will of the Ancients gives 20% spellvamp and 30 AP which is pretty good on akali, but i prefer more tanky items, so i only buy this when i have other champions on my team who can use the spellvamp and AP, since it's an aura effect.

lvl 1-5

from lvl 1-5 you should play fairly deffensive and farm the minions with your Mark of the Assassin (Q ability) and with your Twilight Shroud (W ability)

Against a ranged champion:

If you're against ranged champion use shroud as often as possible to avoid getting harassed. Stay in the edges of your shroud since heroes like Lux will have spells like Lucent Singularity which will hit you even if you're invisible. If you enemy let you near the creeps without attacking you too much, use your Mark of the Assassin (Q) to harass them, while farming with auto attack. If your opponent is harassing you all the time, farm with your mark (Q), and place the shroud a little bit back, so you will take as few attacks from your enemy as possible.
IMPORTANT: You do NOT need to avoid everything since you got 9 potions!! don't be too passive!!

Against a melee champion:

If you're against a melee champion use your shroud offensively (On their side of the minions) to scare them, and to harass them. When facing a melee champion you should always have your mark (Q) on them, and if they try to come close, go and hit them with an auto attack, or your Crescent Slash(E) if you're lvl 3, to keep them away.

Note: If you get your enemy to recall spam all your abilities ALL the time to push as fast as possible. This will result in your creeps going to their tower, and dying 10 times faster than usually, and your enemy will loose alot of farm, giving you a great advantage.

lvl 6-11

As soon as you hit lvl 6, you should start poking your enemy. How you do that, is first to use Mark of the Assassin (Q) on your enemy. In this lvl, your mark should almost always be on your enemy. Then you Shadow Dance to your enemy pressing Crescent Slash (E) immediatly after, damaging him around 25-75% hp in less than 1 second. The energy regained from your mark (Q) should be enough to use Twilight Shroud if you want to avoid taking any damage back, and getting back to the minions in safety.
this combo can also be used to kill your opponent if combined with Ignite or used twice, since there's a really short cooldown on your combo.

Lategame/teamfight

Akali is really good at pushing since she can nuke creepwaves in only seconds. You should stay with your team, but also try to farm when possible (If you don't have full items)
Your role as Akali in a teamfight is to take out the ADC as fast as possible, or their AP mid. basically just the squishy hero with most damage. Besides that Akali is good at confusing the enemies with her Twilight Shroud and maybe even splitting them, making it possibly easier for your team to destroy them.

Worst enemies: (in order of how much they own you)

If you meet Lee sin on a lane you're pretty much screwed. He can damage you through your shroud with his AOE, and all his spells reveal you... When i meet Lee sin, i call for help from jungle, and build ALOT of armor early. I try the best i can to dodge his abilities, and using shroud all the time (remember to stay at the edges) and desperately try to farm with my mark (Q)

If you meet Riven you're gonna have a hard time if she plays well. She can stun, damage and kill you while you're in your shroud. She also have a shield, which she can use while your mark (Q) is in the air, preventing her from taking damage. Call for help from jungle, and farm with mark (Q)

Darius is really strong against akali since the shroud ain't protecting you at all. Whenever you use shroud he will walk to the middle and use Decimate applying Hemorrhageto you, which will just keep ticking your hp down. If he plays well he will stay in your shroud, and if you come out use Apprehend to give you another stack, auto attacking you right after, which will give another stack, and before you know it you're dead. buy Giant's Belt ASAP!!

Garen, Renekton and Pantheon can, like the heroes above, hit you even though you're in shroud. You can avoid the spells Judgment, Cull the Meek and Heartseeker Strike but as soon as you get close to the creeps you will get a Decisive Strike + Judgment from garen, a Slice and Dice + Ruthless Predator + Cull the Meek from Renekton, and Aegis of Zeonia + Spear Shot + Heartseeker Strike from Pantheon, and you'll be harassed to death. theyr'e also tanky, so you can't really harass them effectively. Buy alot of armor, and call for your jungler to zone them early on.

will have alot of magic damage and magic resist, and to win this lane you should build early Mercury's Treads and Abyssal Mask to both get magic resist, and counter his.

Best enemies: (In order of how much you own them)

Karthus won't be able to do anything when you hit lvl 6. Untill lvl 6 you stay in your shroud, making it impossible for Karthus to hit you with his Lay Waste and keep using mark (Q) on him. When you hit lvl 6 you can keep using the poke technique, and get alot of kills, or atleast keep him away from the lane.

Ahris Fox-Fire and Spirit Rush do not lock onto targets she cant see, so while you're in your shroud (W) you won't get hit. beside that, Ahri's Charm will NOT reveal akali in her shroud (W), and it won't pull you out of it. Akali will burst harder than Ahri. Ahri's Orb of Deception is easy to avoid, atleast on the way back, so it won't be harassing you too much.

being against a zyra mid is lovely for Akali. As soon as you hit level 6, Zyra is a free kill for akali and it's hard for her to stop you. Untill lvl 6, just keep your mark (Q) on Zyra at all times, and farm with shroud (W) and auto attacks. When you hit lvl 6 wait until you have 2 ulti stacks. Then you mark (Q) her, and wait for the spell to be ready again. When it's ready you shadow dance (r) her and auto attack her. Immediatly after you apply another mark (Q) and use crescent slash (E) to proc that one. If she's not dead use shadow dance (R) again and maybe even ignite.

Generally akali is a counter against most AP heroes, which makes her a good mid hero.