Okay, as an experienced Nocturne, I'd like to point out that Nocturne is NOT a glass-cannon Melee AD Carry like most people assume. He is an incredible tanky dps jungler who still manages to dish out massive amounts of damage throughout the game. If you're looking to get infinity edge and phantom dancer, go read an ashe guide. Seriously though, if you were to watch any high ELO nocturne like Saintvicous or TheOddOne, they all build Nocturne pretty tanky like myself. It's just more effective this way. Enjoy!

Attack Speed Reds + One Armor Pen Red: quicker jungle. I add the one armor pen red because of the fact that having 12 armor pen and 19% attack speed is better than 20% attack speed and 10 armor pen.

Armor Yellows: Armor seals are just the best for any jungler, makes it so much easier and so much safer. Also, it makes you even tankier!

Attack Speed Blues: I guess you could get cool down blues or magic resist/lvl but I prefer attack speed because your items will make you tanky enough and cooldowns aren't necessary in my opinion.

Armor Pen Quints: Having 10 extra armor pen gives you true damage against most jungle minions.

16/0/14

I just love this set up for Nocturne. It provides you with everything you need in the offensive tree: Damage, Attack speed, Damage to minions, Armor Penetration. AND it gives you some nice utility like the Extra Buff Duration and Movement speed. I wouldn't use any other mastery page.

Wriggle's Lantern is a necessity for jungle.

Mercury's Treads are just better than everything (if you get berserker greaves you aren't doing your team a favor at all)

Heart of Gold is a nice bonus to health. Also, the gold per five is very nice combined with avarice blade. It makes for an easy and quick ghostblade because you won't be farming like most champs.

Ghostblade is just amazing on Nocturne. And it's not just the armor pen and damage, it's about the amazing active that gives you ridiculous attack and movement speed to be used for team fights, ganks, and escaping.

I love Banshee's and Atma's on Nocturne. With all of your items, Atma's gives you a bonus of about 53 damage AND 45 armor. ALSO, combined with Ghostblade your critical strike chance is over 40% which is very nice.

Randuin's Omen is optional, only get it if the enemy team has a LOT of attack damage. If you don't need Randuin's, pick up another item of your choice, preferably defensive.

Bloodthirster: only get this to replace Wriggle's if your game is taking a ridiculous amount of time.

R > Q > W > E

This is a pretty self explanatory skill sequence. Prioritize ultimate like any other champion, then prioritize your Duskbringer, which is a very good AD scaling and long ranged nuke. Next you want to max your attack speed steroid because it gives a great amount of extra attack speed which is always a plus. Lastly you max your fear because you only really need it for ganking at low levels.

Jungle Route:

1. Grab your Vampiric Scepter and head to Wolves.
2. Smite the big wraith and finish the camp.
3. Go kill the small golems.
4. Go back to base and purchase a Cloth Armor and some health potions.
5. Go kill blue buff and use smite.
6. Wolves again
7. Wraiths again
8. Red buff (smite then gank mid if possible, usually it isn't)
9. Mini Golems
10. Go gank now!

You might be able to gank somewhere in between but this route is about getting red buff quickly. If someones below half HP and overextending, feel free to go make them burn flash or kill them.

I like this route because it is very safe, I recommend you have someone watch your blue buff and wraiths to make sure you don't get counter jungled too hard. But it doesn't matter, you're Nocturne, just go counter jungle them as well.

Pros:

Easy Jungling because of passive and attack speed
Tanky champion who can soak up crowd control very effectively
Great damage output as well, while remaining tanky
Great initiation with his ultimate which can synergize very well with other global spells like Ashe arrow.
Spell shield which can save you from that obnoxious Sion or Annie stun and keep you alive.

Cons:

Gets destroyed by high amounts of stuns......sometimes.
Difficult to gank without Red Buff......sometimes.
Ultimate's range is garbage until level 16
People can easily flash out of fear.

(Not very many cons because Nocturne is amazing)

Teamfights can sometimes be tricky for Nocturne. It's all about timing that ultimate, or saving it for a straggler. Sometimes you'll be forced to initiate the fight with your ultimate, that's not a problem because you can easily soak up a couple spells from the enemy team and get out with at least half health. Your goal is to blow their cooldowns and remain alive so you can melt the carries. You most likely won't be focused, which is another benefit of tanky Nocturne, because you get underestimated 24/7

(ALWAYS POP THAT GHOSTBLADE ACTIVE IN FIGHTS)

Well, you are jungling as Nocturne. Laning with Nocturne is just a waste. So, you're going to grab smite because that's what a jungler needs. Now, you may either choose to have flash or ghost as you second summoner spell. I prefer flash because it's the easiest way to escape. But it's just based on player preference.

This build is recommended for Ranked Games mainly because, hopefully, you'd have a good team composition in a ranked game. I have several tips for ranked play though:

-Do NOT get greedy unless your 100% you can get first blood. Any amount of gold the other team gets is not good for your team.

-Also, while ganking in early levels, ask your teamate(s) to do some hard core baiting so you can be sure to land your fear on someone for an easy gank.

-Try to soak up enemy crowd control in late game fights so your carries don't die. If you die and your team get's more than one kill, it's worth it.

Nocturne is an incredible champ. I like to play him as a Tanky DPS because, well, a good team composition should already have enough Attack damage, air-go you don't need to build glass cannon. Nocturne pumps out amazing damage while soaking up an amazing amount of damage. He is a tier 1 champion for a reason. Enjoy :)