Nocturne is a powerful champion with variety of builds.He is a realy strong champion cos his ganks are overpowered and his damage output is really much.I will explain how i suggest you to build nocturne on this guide.

The way i set him is with armor pen red armor seals magic res per level glyphs and armor penetration quintessences.However, taking magic resist or attack speed instead for glyphs and attack speed on quintensesses is also a great choice

The masteries I use are 21-0-9...However, 12-9-9 or 9-0-21 are also a good choice.Dont forget to take cooldown reduction, movement speed and armor penetration, and also enchance your flash spell

5 v 5
What about items...I start with a vampiric sceptler, but starting with cloth armor and 5X potions or boots and 3X potions are not bad choices...The way i set him on my build makes him offtank damage dealer.But there are also other builds I use depends on the enemy team.If you need a pure damage dealer, nocturne can deals tons of damage with the following build:Trinity force, Guardian angel, Mercury treads, Yommuus ghostblade, bloodtherister and infinity edge ....If u choose this build, its really important to take mercury treads as your boots cos you will be A LOT squissy.However your damage output will be too strong...If enemy team has many ap champions, just change your warmgongs with a banshee's veil.......What about boots....I give 3 options about boots, mercury treads berserkers greaves or ninja tabis.If enemy team has many stuns take mercury treads.If enemy team has many ad champions take ninja tabis.And if enemy team has nothing of these 2 things take berserkers greaves.
3 v 3
On this map start with dorans blade.Then buy your boots and your core build should be bloodtherister, frozen mallet, yommuus ghostblade and infinity edge.Your last item is all about you.I prefer phantom dancer or atmas but you can take whatever you like
Why i select these items
1)yommus ghostblade--->It gives you armor penetration and his active cooperates nicely with you duskbringer.Thats the most important item.
2)mercuricy treads--->Nocturne is squissy champions so he needs this boots to get out of cc's faster.I always prefer them from breashekers graves
3)bloodtherister--->As an assasin he is really squissy, but he deals lots of damage.So this is the perfect item for him.He can take hp back while dealing 100 more damage.Dont forget bloodtherister too.
4)Frozen mallet--->Phage is very preety decent item, cos you can slowing enemies while you dealing a lot of damage.However, exept frozen malet you could use trinity force.I usually prefer frozen mallet but trinity would be a good choice too
5)Warmog's--->I chosse this item, because after I purchase it I know enemy team wont initiate on me and i can deal free damage.HOWEVER, if enemy team has many ap champions, ALWAYS take banshees veil instead of warmog's
6)Atmas--->This is the perfect choice to come with frozen mallet and warmogs.It makes you more durable while giving you a lot of ad and critical chance

OTHER GOOD CHOICES
Phantom dancer--->Gives you movement speed so you catch enemies faster and also attack speed and critical chance are improved.If you decide to take phantom dancer, dont forget to take the next item.
Infinity edge--->As an assasin it will help you deal the tons of damage you must deal.However, take this item only if you decide to go less tanky and more ad.Dont take it if you are to go tanky.
Trinity force--->Great choice too.Sheen cooperates perfectly with his passive as it will make it deal even more damage.Phage is on core build and i explained why before, while zeal gives you the movement speed you need to catch enemies faster.
Madreds bloodrazor-witch end---> I dont really like these 2 items on nocturne.I prefer on champions like warwick or shyvana.However, in spefic cases they can be proved good.
Guardian angel--->Its the defensive item that you get when you go full ad.It gives you armor and magic resist and also has a phantastic passive so i think it is really good.
Frozen heart-Randuin's omen---> Those two items works really good on noc only if you decide to be the initiator of the team.If not dont take them.
Thornmail--->Situation anti-ad carry item.If enemy team has many ad champions grap it and watch them killing themselves.

Maximazing duskbringer first is the best thing you can do because you will have more movement speed and damage.After duskbringer max unspeakable horror because you enchance his duration.Take paranoia when you can and max shroud of darkness last.

[For summoners spells I use Flash and Smite
Other great choices would be
Ghost if you thing your q doesnt give you enough speed to catch your enemies.However flash has saved my life a lot of times so i rather flash than ghost
Exhaust If you are the initiator of your team, you will be able to ulti+exhaust on the enemy ad carry, thing that will be devastating for him.
Ignite If you are bored of seeing people escaping with 20 hp from you, take ignite and kill them.Never take it when jungle though, cos you need escape spell.
Even Clearvoyance can be good for you, because it cooperates with nocturne's ultimate.

DO NOT TAKE
Clarity : Even if noc has mana problems early game, he is a late game champion.And clarity is a useless late game spell.So its useless
Revive: Useless spell i dont think i have to explain something
Heal: No point for jungler to take this spell.Its more useful on support or ad carries.
Fortify: Useless spell because of its huge cd.Even if someone uses it in team it must be the tank and not you.

PROS
He is a very fast jungler
He is a very good ganker
There are varieties of ways to build so you can adept on the situations
He is a very good anitiator
His paranoia(ultimate) range is sick
He is really fast when on "q"
CONS
Squissy
He doesnt have abilities with area of damage
He has mana problems on early levels
Can be focused if he doesnt go tanky

Start on wolves and tell your team to damage them.Then immediatly go to blue and smite it so you finish it.Now you are level 2.You have 2 options: 1)you take unspeakable horror and you head for a gank 2)You take shroud of darkness and you keep jungling...If you take unspeakable horror, gank the lane that is more pushed....If you dont want to gank and you want to keep jungling take shroud of darkness.I usually prefer taking shroud of darkness on level 2 and gank after i get rad buff.If you take shroud of darkness, go to wraiths, then red, and then golems.Use smite at the big one.Now you can go back, buy boots and start ganking with more chances for a kill.

Noctrune can escape enemies easily....when someone catches u use w the best possible time to block the spell you need to block.After it fear throw q in front of you so you run faster and while you are doing this fear the enemy behinf you.That will make you escape easily...also when u initiate open ur abilities with this way---> r-yommous-w-q-e....thats the best way to secure kill

Coopearating with your team is very important.If you are playing tanky u can initiate.If u are not, then you must ask a teammate do it for you...Remember, never go first in the teamfight and ALWAYS focus ad or ap carry.If enemy ad/ap carry dies before yours(depends which one is more dead) teamfights is 90% over and you win.

If you want to lane with nocturne, the best way to farm is this: throw q and try to hit all creeps in front of you.After this go at and hit with ur passive all creeps.That will guarantee you all creeps when you reach duskbringer level 5(your champion is level 9)...Till level 9 you have to last hit like without using abilities, which may take some time to get used to.

At ranked games, never lane.Always jungle.People are usually a lot better on ranked games, so go jungling.On solo top noc can be beaten easily by a skilled enemy like ww irelia or riven.But he excells at jungling.I described you above the way you jungle so thats what you have to do.

My name is glikethenoobman and i play on eu west.U can add me if you want.Right now i got 1502 kills 676 deaths and 1482 assists.103 won and 82 lost.He is my main champion and thats the way i build him.Tell me your opinion about my build plz i would like to hear it :)...ty for spending your time on my build:)...I would also like you to tell me how i can upload photos in build because i am new here and i dont know how to do it xD

In conclusion, Nocturne is a really powerful champion.I prefer to jungle with him but you can also lane.Whatever you do, never surrender on early game.His late game pottentian is reallllly strong.Ty for your time:)