Hello and welcome to my Akali guide, I hope you will have fun with it and rock some games with it!

Pros:
- Very good assassin mid and late game
- Good farming
- Amazing lifesteal and spellvamp late game

Cons:
- Kinda squishy, especially early game
- If you don't have a good start, you will really miss stacks
- Tends to be focussed with 2 stack items

For runes, I go with magic penetration as marks and quintessences, it helps you a lot in beating tanks. For seals I choose flat health because Akali could use some toughness at the beginning. For this toughness armor seals are a perfect alternative. For glyphs I choose AP per level, because many of Akali's skills are getting powerfull with AP. Why not flat AP then? Of course not, Akali shines at mid and late game, and at that point AP per level beats flat AP.

For masteries I choose the AP per level one and then go for 1 in crit chance and the rest in magic penetration, as much of your skills are magic. The rest goes in utility since I don't feel defense makes a huge difference. Take good hands and 1 point in perseverence. Don't ask me why, just realise what 4% does with 18 HP regen/5. Yes indeed, thats 0.144 HP per second more regain...
The experience gain, extra buff duration, extra movement speed and improved flash speak for themselves.

Here is the good part. The part everyone scrolls down to, and the part 50% of the viewers only look at. Since Akali is an excellent assassin, you get kills like no other. For this reason also I pick both stack items, Sword of the Occult and Mejai's Soulstealer. Both of these benefit her passive real good. Also do both AP and attack benefit her skills. Also, in long fights Akali will not always be able to skill, so she will do some huge damage output with auto attacks. Also the 20 stack result of both stack items are great for Akali. The 15% extra movement speed give you a better chance to catch up with fleeing enemies, especially when you have Rylai's or Hextech Gunblade. The 15% CDR let your essence of shadows regain more quickly, which may be the deciding part of getting another kill or not. I get the Sorcerer's Boots because I don't feel the need for any other. Mercury treads as recommended? Why? You won't survive 10x as much battles with them! Also for extra movement speed is no need when you got 20 stacks on your Sword of the Occult, the right masteries and Rylai's Crystal Scepter. For the Hextech Gunblade and Guinsoo's Rageblade: Akali is a hybrid, think about that and no further explanation is needed. I also take Rylai's to catch up with enemies. Because when you cast Shadow Dance on an enemy, the distance will be closed, and him or her will have a hard time walking away because of the slow. It is also a great item for if one of the squishies in your team needs some space, you just use a skill on the pursuing character.

I don't have a specific skill sequence, but when I watch what I do, the combo usually looks like Shadow Dance towards the target, Mark of the Assassin, Crescent Slash, and then Twilight Shroud if it gets kinda hot. When it doesn't, I just pop whichever skill is available, and keep on auto attacking whenever my energy is running low.

For the skills itself, level Mark of the Assassin first since it does much damage, also when you got the chance to auto attack an enemy to trigger the mark. Second max Crescent slash, just for the damage. And at last max Twilight shroud, since it only gives more def/magres, and slows your enemy. Of course max your Ulti right away, simply enough for the damage and the restock time.

Last note: Use your Mark of the Assassin early game on enemies to harass if you are pushing, or use it to lasthit minions if your enemies are pushing you much. It is also a good way to restore your health a bit.

I take as summoner spells Ignite and Flash. I take ignite mainly because it helps a lot early game to make that extra kill which counts towards your stack items, and late game for enemies like Mundo, high lifesteal enemies or supporters. This spell can be switched out though if you don't like it very much.

Flash is required for Akali, since it is very good to escape tight situations. Especially when you are in your Twilight Shroud near a wall, you can just jump over it whilst the enemies sometimes dont even notice it.

As you know there are a few positions in your team. In my opinion the best is to go on a side lane with a teammate. My next choice would be mid solo. Other options, like solo a side lane, or jungling should be left alone. As I already have said, Akali is squishy early game, and will have a hard time without a teammate.

- When you have finished your Hextech Gunblade, and you are being chased by 1 or 2 enemies while you are on low HP, don't keep on running if it's a long way. With Hextech gunblade, a bit of energy and 1 or 2 stacks of your ultimate you could just keep your life up long enough to kill your 2 chasers. Never do this too clearly though, always start doing this from inside a bush.

- Not dieing is a priority above making a kill, like any champion, but especially with this build since you have 2 stack items you depend on partially. You can't afford to loose too much stacks.

- This build is fairly cheap, considering the stack items aren't expensive. When you got full stacks with all elixirs, you would almost be able to solo Baron (if not fully). So when there is an opportunity, tell a teammate to come with you while the other 3 distract the enemy, to get a unexpected Baron Buff for whole of your team.

- When you can see your death coming (like Karthus' Requiem, Vladimir's Hemoplague, or Zilean's Time Bomb) never forget to cast Twilight Shroud, as it gives you 50 extra magic res and armor. This can just be enough to save you from dieing.

Sorry for the lack of decoration on my build, but im kinda new to making builds (this is my first one). I would like to have some feedback for if I maybe forgot a section, or you would like me to make a specific one. I will try to put up some screenshots of my last matches, and maybe some replays, but since I play a lot of different champions this might take a while.
Thanks for reading my build, and have fun with it!

P.S.
My native language isn't English, I tried to do my best writing this guide in correct English, so please no stupid comments that I should take English classes or whatever.