Hi,
Thanks for reading this guys :D
Don't feel bad criticizing the guide because constructive criticism is always good^^
Would like to thank Noblesse Tr, Prodigy75, Grogolog, Nighthawk Theo and HappyTron for being Awesome :D

Well.
I take Armor Penetration REDSbecause it's basic for any AD melee out there and will help nocture rape everyone even tanks^^
I take Mana Regeneration per level YELLOWSbecause poor nocturne has a horrible Mana pool and the cost of his abilities suck very, very hairy balls. These will help you stay in lane for longer as you wont have to recall for mana or buy mana potions at the start.
I take Magic Resist Per level BLUESbecausesince nocturne is generally quite squishy till mid to late game against casters he will need these.
Well the Quintessences are up to you. armor pen if you want more damage, or flat health to help him in the early game since he is rather squishy. I personally take the health ones for the reason I just stated^^

Since my build doest have full damage items... Nocturne will need 21/0/9. I choose this for the maximum damage output from his abilities since they can be a real help to nocturne especially with the cooldown reduction. What difference does 3 damage make compared to your spells penetrating 15% of their magic resist :D
I chose the ones in utility because since his mana pool sucks the increased mana regen rocks :D you cant go wrong with getting more experience. I chose the increased gold regen becuase the 1st 2 items as you can see are very expensive. This mastery with your minon farming (which I will get on to) will make these 2 manageable, if they are not you are doing something wrong :D

THIS IS VITAL FOR YOUR VERY EXPENSIVE ITEMS!! Try to last hit as much as possible... my advice is do not lane with maser yi, nunu, veigar and morde as they will steal yoour precious creeps :D

You must harass with Q against the squishiest person in your lane then when you fell that they are at a manageable amount of health. Make their pants dirty when you press R, followed by E and a quick Q so they dont go anywhere in a hurry, dont forget to ignite^^ Always lookout for players who are low... if they are tower hugging, ulti in finish them off, ghost or Q out and use your shield in case there is something like caitlins traps or if veigar or sion come from nowhere^^
When they approach you in the bushes unaware. E as soon as they are in range. Q and your dmg and ignite should do the rest.
REMEMBER IF THEY ARE MOVING AIM Q SO THAT IT WILL HIT THEM!!! AND RUN IN IT SINCE YOU WILL RUN LIKE USAIN BOLT!

Recommended:
GHOST. This is great for getting across the map quickly, getting in range of player for your ulti before they dissapear into in game fog. Also freat for escape with your Q.
IGNITE. This is awesome because this badboy doest have constant damage on his enemies so this is a real bonus. Also great for finishing people off and awesome against tanks^^
Other Viable Options:
Flash. Good for escaping sticky situations.
Clairvoyance. Someone is low and they go into the fog and you want to ulti to them. This has a short CD and is good. This shouldn't be necessary if your team is warding properly.
Clarity. Not needed with nocturnes runes and masteries.
Exhaust. Meh... Like you wont be able to catch them.
NO:
Heal. NO!
Rally.NO!!
Teleport. WTF NO!!!
Cleanse. 2 shields.
Smite. Jungling only.
Revive.<----???? Only when you feel like trolling.

I start off with a dorans blade becuase it gives nice harassment early and gives you a bit more lifesteal off your passive :D
Then depending ow long i can stay in lane without getting low on health, i will either buy a B.F sword if i have enough money, or I will buy boots of speed alone and save up for a B.F sword. I choose a B.F sword early since it gives you crazy damage early game.
Then I go into berserker greaves, or if they opponents have thousands of stuns, snares... whatever I will take Mercury treads.
Then get vampiric scepter and upgrade to bloodthirster ASAP.
now since you should be farming even more that what you were at the start to stack your BT up... you should save up for another B.F sword, then get pickaxe... you dont have any crit anyway by this point so there is no point getting a cloak of agility first. Upgrade all of these into an infinity edge.
Next is banshees veil since it will be like being able to use your W twice.
I choose guardians angel next selling dorans blade somewhere in the process. Now not only do you o awesome damage you are past the armor and magic resist tank cap of 150... (after 150, the damage reduction scales less)
Then to put the cherry on top of the cake i make a phantom damncer for more crit and needed movement speed. Also beast attack speed.
If the game goes on long enough you can sell your boots and make another phantom dancer so you will be quicker and do more damage :D But it is very rare you get to that stage^^ You should have won already :P