Welcome to my Nocturne Build. Instead of the introductions and stuff lets jump right into how to play as Nocturne, and start racking up kills.

Dark With A Chance Of Pain (You're welcome Naberius :P)

Lets talk about the pros and cons of Nocturne that I've found to be a Problem and a Blessing.

Pros

A VERY strong fighter once built
Good Jungler with help from his ultimate.
Can weed out invisible players with Duskbringer
Can kill escapees in teamfights.
Can stay alive with Umbra Blades' Lifesteal.

Cons

Not many tools of escape, except for his ulti but that either brings you too another enemy, or changes the direction of the fight once the Paranoia dissipates.
If Nocturne doesn't get fed, Good Luck. Its Difficult to get it back. Early game dominance is key.

Umbra Blades

Every 10 seconds, Nocturnes attack will attack surrounding enemies for 120% physical damage, healing based on how many enemies hit at once. Nocturnes basic attacks reduces the cooldown by 1 second.

To put this into practical situations, at early game when auto attacks are the most important (generally auto attacks are most important early game because after you've used your first ability, whoever has the stronger attacks in your winner), with the lifesteal from the blades, if you can make the fight last longer than 10 seconds, you've won it with your lifesteal (providing it was 1v1). Generally any fight longer than 3 seconds ends in both players retreating, unless one is clearly winning.

Use the Umbra Blades to farm through minions (What I do is, when its off cooldown, I stand in the middle of the minion wave and strike and get the max heal out of it)

Duskbringer

Nocturne throws a shadow blade that leaves a Dusk Trail. When a target is hit by this, it brings the trail with them for a period of time. While Nocturne moves on the Dusk Trail, he has increased movement speed and attack damage.

A very effective move that can be used both offensive and defensive (the defensive I dont see many people use to be honest). Obviously if you've played Nocturne, you can see that the Duskbringer is a very good attack to have starting because it has range, which is an advantage if you're fighting ranged champions. Hit them with it, run through the trail, make them run while slicing them to bits. Some people forget that when you're fighting stealth champs, you can use Duskbringer to see them. The trail follows ALL targets.

The Defensive aspect of this is, the trail gives movement speed. If you're getting chased, fire it in the direction you're going and run along it. It might be the difference between a death and a recall.

Shroud Of Darkness

Nocturne passively gains attack speed as this ability is leveled up. Upon activating the ability, Nocturne creates a magical barrier and blocks an ability (just one blocked). Upon blocking the ability, Nocturnes attack speed gets doubled.

This ability is your lifesaver. I can't count how many times this has saved me from ulti's, fatal abilities, and helped me win fights. Its already handy enough having the passive attack speed. So I put you in the situation, you're about to fight someone, you're both taking chunks of health from each other, and you can somewhat guess that an ability might be thrown in the mist of this fight (you know it will happen because we all know you'd do the same), Activate the shield. BAM!! you blocked it, you took no damage, and now your speed is now increased, and your Umbra Blades are being cooled faster.

You could even be on low hp, running for your life, and here comes Ashe's Ulti. "OH NOES!" I hear you shout. Throw on the shield, and shout "TROLOLOLO" you've just survived.

Unspeakable Horror

Nocturne "plants a nightmare" into the targets head. Dealing damage over time, and if the target stays in close range (you'll know if they are still in range with the beams that indicate distance) they become feared.

If you combine this attack with what you have so far, you'll butcher anyone who comes to fight you. You jump into the fight, and fear them while hitting them. They cant do much but hope their teammates will help. Usually used as a fight starter (if you dont have your ulti, if you have your ulti, then this ability would come second).

Another way to use it, lets say you're chasing someone, and you're close but not close enough to hit them. Use Unspeakable Horror, and they start taking damage, if you're close to them for long enough, they get feared, then then you've definitely caught up.

Paranoia

Nocturne reduces the sight radius of enemies, making you unable to see your teammates positions. Nocturne can launch himself at the target (within a radius).

If you're a jungler or not, this is a valuable ability. Its obvious use is to cause damage onto a victim at a distance that you dont like. Another advantage of this ulti, is that, when you activate it, about 80% of players will run to their turrets to escape even if they aren't the target.

Summary

Ulti at the victim, Unspeakable Horror so he cant move, Duskbringer for the initial damage and increased damage, pop the shield to block an ability, increase your speed, Umbra Blades will do the rest.

Ok Im pretty sure you've seen this typical build on every dps champ. You can try it with two bloodthirsters, or the two PD's. Both ways will either improve your Umbra Blades, or your passive speed you get from Shroud of Darkness.

Im sure you can throw your own mix in and have a Ghost Blade in there, but personally I only use it for Master Yi w/ Highlander. And dunno if its just me, but when Im in one of those panicky situations, you know those ones that you start pressing every button you have, the tv starts turning off, the radio plays, you're pressing everything to kill, thats when Actives aren't on your mind. Dunno if its just me, but if actives are your thing, throw a Ghostblade in there. Go on you cheeky devil.

This is only my second guide, I dont think I need to go into laning tips or anything. Nocturne is a 6300 champion you obviously play enough to know what to do.

Let me know what you think.
Thanks!
- SapphireDusk