Ok, this is my first build on Mobafire so please don't be rough on me.

I use this build for laning, jungling you can try but the main point is, this is mostly for laning.

Since Nocturne's a squishy character, I recommend playing it safe until you get your whole build, that way you can blitz through anything that comes at you.

Ok so you see the items I recommend and you're probably wondering why there are only five items.
Well the sixth item can be anything your heart desires.

Any of the following items are also good to use in combination with this build

- Frozen Mallet - For additional health and the slowing on-hit effect

- Youmuu's Ghostblade - For increased attack and movement speed

- Banshee's Veil - Magic resistance and an extra spell shield

- Madred's Bloodrazor - Armour, attack speed, attack damage and the extra magic damaage equal to 4% of the enemy's max hp

- 2nd Infinity Edge/Bloodthirster - Increased self-sustain with better life steal or enhanced damage

- Ionic spark - Attack speed and passive "chain lightning" attack

- Wit's End - Increases Magic resistance during the heat of battle

- Tiamat - For more aoe to compliment Nocturne's passive ability

Also with the boots, any will be acceptable depending on your situation. However, in a normal game, I recommend Berserker's Greaves for greater attack speed.

Alright, so for masteries I go 21 - 0 - 9.

Offensive masteries are pretty self explanatory, you want to basically hit the enemy as hard and as quickly as you possibly can. The point on Summoner's Wrath is optional though, depending on your preference on summoner spells.

Defensive masteries I don't see much of a point in but if you want to get them, I'd recommend mag resist, armour and hp bonuses (seeing as you'd only have 9 points left to spend).

Supportive can also vary on your fancy. Getting Expanded Mind can be helpful for spamming your Q. After the first 4 points, you can pretty much experiment with everything below it. Again, getting Meditation will help spammers and Scout helps in cases of opponent junglers and ganks. Runic Affinity is a must because getting blue and red buffs will help Noc a lot.

Although I recommend using Exhaust and Ignite, any two spells can be useful.

Barrier - A good spell for some extra (temporary) hp. Good for any of the big fights and when you're in urgent need of a quick boost, either this or Heal would be good to use.

Exhaust - This is a very helpful spell, either against fast or slippery champions or for taking them down more quickly (if you have the mastery, Summoner's Wrath).

Garrison - I don't usually play dominion, so I can't say that whether or not to use this spell as I have no experience with it.

Ghost - Helpful to catch up to fast champions but redundant, especially if you aim your Duskbringer just right.

Heal - A good spell to keep you in the game for longer but I recommend letting the supporters take this spell instead of you.

Revive - A very rare spell to use as there's not much point to it. Although you can use this spell in dire situations like when you're teams aced and you know you can defend while everyone else respawns.

Smite - Good for jungling... Need I say more?

Surge - You can use this for the bonus attack speed but not as useful as other spells.

Teleport - A good, quick way to get to places quickly like towers or the enemy base.

Cleanse - Helpful for getting rid of those pesky stuns, fears and whatever else that ails your champion

Clarity - A good mana replenishment source

Ignite - Good for taking care of any remaining health on enemy champions. And if you have Summoner's Wrath, the bonus 5 attack damage can be very good at times.

Promote - From what I've seen of this spell, I don't recommend this spell since you're more likely to take care any turrets than any random siege minion.

Clairvoyence - A supporter spell, you don't need it.

Flash - Another useful spell you can have to get close to enemies or out of sticky situations.

Pros

- Couple with Nocturne's Paranoia, you can easily lay waste to any enemies you gank

Cons

- This build tends to leave you with less health than what some AD carry's may like, so caution is necessary