Hi, I am sleepydrone, better known in game as pentablade. Today I am doing a build around nocturne. A ad tank. He can be very versatile, but this one will be around Attack Damage.
Nocturne

Pros
High Damage
Amazing Attack Speed
Anti Mage
Global Ulti

Cons
Melee
Besides His Duskbringer no ranged attacks
Moderate cooldowns(Not a big deal, noc is more of a auto attack guy)

Flash-Good for running, Ganking, a must.
Ignite-i prefer this over exhaust if your not in ranked, you can get an easy first blood.
Exhaust-if you are in ranked, use this, with your Paranoia flash and exhaust,a great gank.
Ghost-Its okay, good for running, and Ganking.

Teleport not the best, flash can be more useful.
Revive 9 minute cooldown? Not really worth it.
Fortify This is more suited for tanks.

Everything Else-Not Worth explaning, Besides Heal everything is worthless.

Duskbringer Q- great all around skill, use it all the time, when ganking put Q down, it raises movement speed, plus, if you are on it, it gives you extra damage. Big Plus, Max it first.
Shroud of Darkness w GREAT anti-mage skill. It gives you attack speed, and when activated gives you a block against a skill, also, the attack speed passive is DOUBLED great.
Unspeakable Horror e, great CC, it can fear, and does damage over time, raise it at a low level, max it late.
Paranoia ULTI, such an amazing ulti, gives great ganking posibilites, does major damage, and can do wonders if you use Duskbringer then Unspeakable Horror for great bursts.

This build is to maximize damage output very fast, with good CC and and Cs.
Duskbringer is used for damage and speed, very good, max it first.
the either two skills is maxed at your preference, I recommend Shroud of Darkness because much of your CS will also come from that.

Simple, ones people go for, damage crit and attack speed with armor! :)

These runes are meant for AD, giving noc major damage, attack speed armor pen and critcal strike, based around my items as well, your spells match great with these runes and items!.

Both your Duskbringer and Paranoia are affected greatly.

Damage Build
Berserker's Greaves
Youmuu's Ghostblade
Frozen Mallet
Black Cleaver
Madred's Bloodrazor
Bloodthirster
^^ this build is meant for damage, Soon I will make a tanky build. This is made for attack speed and damage, which goes well with my runes and skills.

The heart of gold and philosophers stone is used not only for their amazing stats and cheap cost, they give money per second, quickly playing for themselves.

The best thing to do for Nocturne is to last hit the creeps, do not attack them until they are at low health, until Shroud of Darkness is at a high level, you will be missing most of your Cs.

Also, your Duskbringer is very very good, for farming and harassing. Use it a lot!
You can also use your e to prevent the other team from out csing you!

Ask your mates when they need to gank, use Paranoia to start the fight, then Duskbringer, then Unspeakable Horror for fear.

Help out your teamates by tanking some of the damager, a frozen mallet will give you damage health.

Normally, you should jungle noc, this build is meant more for non ranked, but if you are playing ranked, I prefer jungling, i will make a build for that soon! :)).
For now though, nocturne can gank after you get red and blue. at around level 4.

So that is it :) Nocturne is a heavy Dps hitter with good cc, and with a Frozen Mallet you can have all of it, with slow and tanky!. Thanks for reading my build, and this is Sleepydrone, know as PentaBlade!