This build focuses on building Nocturne as an assassin while giving him quite the amount Armor Pen so squishy targets die faster or to duel tanks better since you'll also have BORK in this build. To clarify, an assassin is someone who who can quickly move to and kill a squishy target in a short amount of time while having almost no defensive power which is the drawback and the obvious flaw to this build. However, in my opinion I think building as an assassin on this champion makes use of his kit better than building as a fighter. If you want a fighter than just play another champion because I'm pretty sure there are a lot of ones out there who can build that way better than Nocturne. If you have it, equip the Eternum Nocturne skin because it feels smoother on auto attack animations than the Classic(in my opinion) and gives you more of a happy feeling when you kill someone in an online game.

* W(Spell Shield) can turn any duel to your favor and diminish the power a bursty champ can deal to you allowing Nocturne to assassinate without worry.

* His fear(E) lasts a while once more points are put into the ability giving Nocturne the edge in a duel as well as more movement speed, when the fear is successful, to assure the target doesn't escape.

* With Q's, E's, and Youmuu's movespeed gain, Nocturne can make up for his lack of dash/blink abilities in order to catch up to his foes and prevent himself from being kited.

* Attack speed coming from the W(especially with a successful block with the spell shield) and the items being built for Nocturne, in this build, synergizes greatly with the bonus AD you get from the trail from his Q. The attack speed also in a way lowers the static CD of his passive since each auto attack lowers it by 1 second.

* His ult is a good way to move past the enemy frontline and into the back to rid of high priority targets. This is useful against ranged spell casters like Xerath or Lux.

* Nocturne's ult gives you at least a 4 second window to kill a target by him/herself due to its ability to reduce sight vision and remove shared vision(assuming the target can't type really fast for help or he/she doesn't have a means of vocal communication allowing them to communicate with their team).

* No dash or blink abilities unlike other assassins.

* Only one CC move and it is single target.

* Difficult to get back into game if behind.

* As he provides little CC, Nocturne is a little dependent on how his team can kite/defend their own carries. Even if you manage to kill 1 or 2 of their carries by engaging Nocturne's ult, you are leaving your own backline defenseless and may result in your whole team dying.

* Nocturne's ult can possibly be countered by great communication. This includes really fast typing in chat from the target of Noc's ult or vocal communication(e.g. Skype). This can put Nocturne in a disadvantage in ranked 5v5 or ranked in general(when other team has 1 or 2 duos) since ranked 5 teams or duos usually use vocal communication.

Since you are Nocturne, your sustain is bad so you need a jungle path that won't be suicidal. If you are in the blue team then have your leash start at Krugs(smite here to get the stun proc)-> Red -> and finish at Wolves to move on to your first back(recommend smiting the Wolf for the vision so if you back or do Blue and someone comes to invade, you and your team can react to it). By then you should probably be able to get your Ranger's Trailblazer and 1 or 2 health potions. If you can do Blue or gank, (because you have enough health to do so due to exceptional leash) then go for it. If you are in the purple team then have leash your start at Gromp(smite for that minor poison buff)-> do Blue -> then smite and kill Red Buff.

When ganking, keep in mind for how your prey's abilities work so you figure out when to W(Spell Shield). It is important to land you Q so you can actually chase your prey. Use E first when ganking and then Q when you know you can't miss(focus on this part because your Q is important to the gank) or use E first then when the prey gets feared by E use your Q so there is no way you can miss. If you have your ultimate, then use the mentioned steps above after you ult and make sure you are out of locked screen(players who ult as Nocturne in locked screen tend to miss their Q completely after they ult).

At this point you want to first look out for enemies farming alone in a lane or jungle and kill them by engaging with your ult. You can also bait them out by pushing a lane in then wait for the enemy to push it back/farm. When in a teamfight, wait for the moment like any good assassin should. Your target should be the person/people who are carrying and, even better, if they are squishy. When they are done for, the enemy team may start losing the fight since they lost the person/people who deal damage and collapse.

For combos there is nothing to difficult since your E and ult are point and click and most of your damage will come from auto attacks. Remember to keep in mind of who you will be fighting so you can Spell Shield in the key moments.

Initiate with Q combo: Q and if it lands-> move to your opponent and E-> throw out the auto attacks.
---Yes it is very simple. You can use this while covering a lane and if you land Q or when waiting for a victim in the bush.

Initiate with E combo: E the opponent->throw out autos while waiting for the fear->Q while the opponent is feared and throw out more autos.
---This is the combo I mentioned in 'Ganking'. If you believe you can do it then you may Q before the fear goes off if you know you can land it.

Combo with ult: Press R->Press R again while having your cursor focused on your target->Q at target location during your ult and just before you are about to land(note: you can use your Q mid-ult so take advantage of this so you don't waste time having to cast your Q when you are already in auto attack range of your opponent)->E for the fear->throw out auto attacks.
---This gets the job done when assassinating a target farming alone in lane or in solitude in his/her own jungle. Requires focus and out of locked screen so you can land Q since you are casting Q during your ult.