Ok so I have been playing Akali for quite some time now and I must say she is one of my favorite assassin (and probably my most overall favorite) champ to play.

Pros:
- Great nuke damage
- Good chaser
- Good natural escape skills
- Great harasser
- Great hybrid champion

Cons:
- Somewhat squishy
- Difficult to farm
- Can be shutdown with lots of CC
- Sometimes requires good awareness of your environment

Twin Disciples
This passive is what makes Akali a viable and great hybrid. With the right runes, items, and masteries, this amazing passive will be up and ready at level 1.

Mark of the Assassin
This ability is her main damage dealer and nuke. Just using this spell with an autoattack will make most enemies run in fear. A good trick is to use it, wait until it is up again, autoattack to get rid of the first mark, then use it again for a double amount of burst damage.

Twilight Shroud
This is Akali's ability which makes her a great ninja. It is also the only stealth in the game that instantly stealths and gives extra armor and magic resistance. Good for slowing enemies, 1v1 fights, huge team fights, facechecking brush, and flashing out of it. Be careful though, as it takes a large amount of energy to use, so make sure you know how to conserve the energy you get back from your Mark of the Assassin.

Cresent Slash
One of Akali's best farming tools for late game. Not a huge amount of burst, but still better to upgrade early instead of Twilight Shroud so that it makes it easier to farm. This is Akali's only AoE ability, so it is best used inside the middle of a huge team fight to make sure you get the most damage off.

Shadow Dance
This is what Akali what she is, which is a true assassin ninja. This ability has so many uses: Use it to get a quick gank in, to last hit creeps, juke out enemies, and chase like a madman.

Ghost - Most people laugh at this skill when I use it, because they feel that its not needed with her Shadow Dance and other slows. Well here is a little secret, some people have speeds, slows, and stuns of their own. You will not always have the privilege of just hitting Q>R>autoattack>E. This spell is just to ensure that you will be able to catch up to those tough champs that just wont gtfo.

Flash - This spell should always be with you when you play as Akali. Someone jump over a wall? FLASH. 3 people surrounding your Twilight Shroud like a pack of hungry wolves? FLASH. Someone just out of range of your Shadow Dance? FLASH. Do you understand now?

OTHER SUMMONER SPELLS:

Ignite - While this is a good way to ensure your kill, I feel that Akali does not need it. You have moves and other things such as item passives that will ensure you will get the kill. You should not need this.
Exhaust - Good for those ***s like Teemo and Tristana who think they can kill you from autoattacking and then running. Show them whose boss with this spell.
Heal - I have seen this used by some Akali's while in their Twilight Shroud to fool some people into thinking they have them cornered. I guess if your into this spell and you feel like you do not have enough survivability, then go ahead.
Smite - You should not have a HUGE problem farming with your Mark of the Assassin and last hitting. If you plan on jungling then this spell is great. If you plan to lane, then don't.
Teleport - Great for getting back to your lane and quickly teleporting to a team fight. I have seen it used for teleporting to secret wards in order to catch enemies or set up a secret gank. If you need to have this then go for it.
Cleanse - Akali is very vulnerable to a lot of CC and whatnot. This spell works well if you get slowed or stunned in a very unfortunate situation.
Revive - Waste of a spell and will leave you with only 1 spell for 10 minutes.
Clarity - Trololololol.
Clairvoyance - Have seen it used for countering junglers and finding you low-healthed enemies, but there are better spells to get.
Fortify - Leave this to the tanks.
Rally - No, just no.

Marks - For marks I take magic penetration runes as Akali will deal magical burst damage from all of her skills. It will also help with the tanks that stack so much magic resistance against you (and sometimes only you, so feel special).

Seals - For seals I take dodge runes. Akali already has her Twilight Shroud, so it can't hurt to get some dodge percentage for that lucky taunt Rammus gets after you unstealth.

Glyphs - For these I take flat AP runes. This plus your Quints will help activate your Twin Disciplines at level 1.

Quints - For these I take 3 of the best flat AP Quints there are around. This plus your glyphs will make your one of your passives is already activated at level 1, giving you an advantage on your damage.

With Akali, I feel that it is best not to go with a 9-0-21, 9-21-0, or any other similar/standard builds for her. I go with a 13-16-1. I go with 13 in offense to get the extra magic penetration/armor penetration and the 1 point in Brute Force to help activate your passive with a Doran's Blade. The 16 in defense helps with her survivability (some armor/MR and extra health) which helps keep her in a lane longer than normal. The 1 point in utility is just to help upgrade your Ghost spell for longer chases.

Doran's Blade - This item is a great starter for Akali. Even though you are now not able to get any pots with a Doran's item anymore, I still feel that the lifesteal, extra damage to upgrade your passive at level 1, and the extra health is a lot better than getting, lets say, a Long Sword.

Boots of Swiftness - These boots are by far the best boots for Akali. She is an assassin, and therefore needs a good amount of speed to help her chase and/or escape. Some other acceptable boots are Ninja Tabi (for extra dodge or heavy AD/DPS teams) or Mercury's Treads (for heavy CC teams).

Hextech Gunblade - This is definitely one of your core items. The life steal from the Hextech Revolver will help you a LOT for early game, and the Hextech Gunblade will help you with your damage output and survivability mid-late game. Akali also loves hybrid items such as this, which will add attack damage, ability power, life steal, and spell vamp.

Rylai's Crystal Scepter - This will be another one of your core items. The health and ability power on this item is just too much to pass up. But the real thing that I love about this item is the passive. Dealing spell damage to a target will slow its movement speed by 35% for 2 seconds. I love hitting someone with a Mark of the Assassin before they hit their Ghost, which gives me just the right amount of time to get in range for my Shadow Dance.

Lich Bane - To me, Akali feeds off of items with great passives that help with her burst damage, and this item just adds to that list. With the 30 magic resist, 80 ability power, and 7 movement speed, you would think of this as just a normal "good" item for her. Wrong. The passive on Lich Bane is what turns her Mark of the Assassin, into a OMGWTF BURST DAMAGE move.

Guinsoo's Rageblade - Again, another great hybrid item for Akali. A Guinsoo's Rageblade is just like telling your opponent "The more you fight me, the stronger I get." This combined with the rest of your passives will just shred through your opponents.

Frozen Mallet - Another good slowing item, with a little bit of attack damage and health to go with it. This item for me is more of an item that I get for a really long late game where the extra health just lets me go to town on the other team for a longer period of time.

Ok, so you spawn, get your shiny new Doran's Blade, and head off to a lane. Get some farming going with your Mark of the Assassin/autoattack combo. Get some harassing in too with it and pull it off for some good early burst damage if they get too close to your Twilight Shroud. Try not to go back until you can get your Hextech Revolver, Boots of Swiftness, and a couple health pots. Make sure to harass with your Mark of the Assassin. Once you get them low enough and you hit level 6, go ahead and go in for the kill. If you have your Hextech Revolver already, you should only need to get them down to about half (most squishies at least) or a little lower for tanks. Once you get some kills go ahead and buy your Rylai's Crystal Scepter and then start working on your Guinsoo's Rageblade. In team fights toward mid-late game, try to stay in the fight, but out at the same time. Unlike an Evelynn you can sometimes stay in a team fight for longer periods of time. Try to place your Twilight Shroud not directly in the middle of the fight, but a little on the edge of it. This gives you time to keep using your Shadow Dance to initiate in and do some burst damage, and then run back to your shroud for safety if needed. Also, if you are able to chase off some low health enemies, go for it. Just don't forget one thing when playing Akali, your spell vamp and damage are greater than you might think. If they are low enough, you might be able to tower dive them and get away with it. Also, make use of tower diving if you have Ghost and/or Flash up.

Thank you all for reading my Akali guide, and I really hope that you learned some things. Just remember that everyone has a different play style and you don't always have to use this exact build. Experiment a little! I find it fun to use a Will of the Ancients sometimes instead of a Hextech Gunblade. Just use what you need. If you need armor then get some, if you need more health then get more. Just use the main core items if you have too. Play to how you play best.

Videos coming soon!