Welcome to my Nevermore guide. It's my first guide, and I'm bringing out MY thoughts on how to play nevermore, along with some standard tactics. I believe i'm very good at english, even though it's not my native language, still, feel free to pont out any spelling/grammar errors. I'll try not to have walls of text, and make everything as straightforward as possible.
Please comment and rate. Try to do constructive criticism, not just "noob guid fail 1/10", tell me why it isn't good, i'll try to correct it.

Contents:
1.Introduction
2.Spells and spell build
2a.Shadowraze
2b.Necromastery
3c.Presence of the dark lord
3d.Requiem of souls
3.Items and item build
3a.Starting
3b.Core
3c.Luxury
3d.Situational
3e.Rejected
4.Gameplay
5.Closing word

1.INTRO

Hero page for all the details:
http://www.playdota.com/heroes/shadow-fiend

Pros:
-Partially flexible
-Amazing damage potential due to Necromastery and Shadowraze
-Amazing ultimate in teamfights
-Fairly high stat gain
-Transforms into a carry late game, while being extremely effective early game
-Can cause massive destruction with proper items
-Not entirely item dependant
Cons:
-Useless if in wrong hands
-Very fragile
-Fairly low starting armor
-Can have a hard time farming early game, before he racks up souls with necromastery
-Lower agility gain than other AGI heroes

Simply put, in hands of a good player, Nevermore owns. In the hands of a bad player... not so much.

2.SKILLS AND SKILL BUILD

Nevermore's bread and butter are his skills during early and mid game. He can dish out a total of 900 magical damage with razes, has a free +60 damage, and can turn the tides in teamfights with his -armor aura and ultimate.

2a. Shadowraze

Shadowraze is a crucial skill for Nevermore. If you don't know what it is, it allows you to do AOE damage in front of Nevermore, at 200, 450 and 700 range in front of him. When learned, gives 3 skills, one for each distance.

Shadowraze gives Nevermore the edge over other heroes early game. By the time you hit level 8-9, you will have 900 damage on your back. That's better than Finger of Death/Laguna blade/Dagon (all of those at level 1), assuming, of course, all 3 razes hit.

The Z,X, and C keys represent the distances at which the raze will be fired, z being the closest and C being the farthest.

The Z raze is the simplest to do, since it's basically at melee range.
The X raze is a little trickier. It's range is almost equal to Nevermore's attack range, so begginers usually like to attack the target first, then press X.
The C raze is the farthest, and the hardest to land. Think of the distance between the two sides of land at the river at mid lane. You can basically hit your oponnent from the safety of your side of the lane.

Two correctly positioned razes clear out an entire creep wave.

Razes do not damage magic immune or mechanical units.

You need to practice razing, because it's a crucial skill every Nevermore player must master.

2b. Necromastery

Basically, everytime you kill (last-hit something), Nevermore stores the creature's soul and stores it inside him, using the soul(s) to amplify his own attack power.
Half of the souls are released upon death.
Each soul gives +2 damage, up to a maximum of 16/30/46/60 bonus damage (7/15/23/30 souls).
A good way to get your souls back after death is to go jungling weak camps, if you have lifesteal, or simply raze a creep wave twice, for 6 souls (+12 dmg).

Necromastery gives you a significant early/mid game dps boost - try to die as little as possible (you are a semi-carry after all).

2c. Presence of the dark Lord

It's (almost) a free desolator aura. Also works great with deso itself. Very useful in teamfights.

It's very doubtful whether to get Stats or PotD. If you had a very good game, haven't been dying, get PotD. Any other case, get stats cause of the survivability.

2d. Requiem of souls

Your second most important skill. A succesful requiem with proper positioning can turn the tide of a team battle.
Here's how it works: When cast, there's a 1 second animation, after which nevermore fires evil souls from him in a radial pattern, number of souls being equal to half the number of souls from Necromastery. In other words, it works well only when you're racked up with souls. The mos important thing about it is that souls lose power when moving, and only the nearest targets will get the full damage of a requiem. A target standing right next to Nevermore will get hit by 2/3 souls, equaling approx. 160-540 damage, depending on the level of the spell (80/120/160 damage per soul)

It needs a lot of utility items to be set up properly: almost half of your core is designed to set up a great requiem.

It is possible to do a so called "Perfect Requiem", when you are actually INSIDE your targe, via Phase boots/ Lothars. The target would get hit by all of the souls, equalling somwhere about 2400 (!!!) damage, more than enough to finish off almost any agi/int hero even mid/late game.

3.ITEMS AND ITEM BUILD

Not much to say in global, so i'll just move on to the specific sections:

3a. Starting items

1x Slip
3x Branch
1x Magic stick
1x Tango

I like this one. Balanced stats, magic stick to upgrade to wand, 1 slipper just because :P and 3 tangos is just enough if you play correctly (passively).

Feel free to do any other combination.

3b. Core
Notice that a good half of it is intended for survial, and another half for setting up a good item. You'll sell some of these later for your luxuries.

Lothar
BKB
Blink
Wand
Bottle
Treads

Now:
1.Lothars for several reasons:
-Unmatched survivability
-Irreplaceable for setting up requiems
-suprise element
-nice damage and AS

I make this item in 98 % of my games with nevermore.

2. BKB/Blink

If you don't make Lothar's, make these. Blink is better than Lothar's in only one thingositioning. BKB is a must if you are playing against an even mildly skilled team-you're a carry, you are a threat, and you WILL be focused. Get it if you have trouble.

A BKB is necessary to land a requiem with a blink dagger.

3. Wand/Bottle: You need cheap mana/hp heals.

4. Treads: absoultely every time. Put it on STR. The stats are something awesome for you, and you have some bonus MS to land that last raze in a chase.

3c. Luxury

Oooh, you're a big boy now. You need the big guns:

MKB
Buriza
Desolator
Butterfly
Satanic

This is what i usually get.

1. MKB: A fantastic dps item. Goes well with your AS.
2. Buriza: Get this if you like to hear things like "M-M-M-MONSTER KILL","HOLY SHIIIT", etc.
3. "Corruption, destruction!" Slipknot-"The Nameless" (i think)
4. Butterfly: Obvious reasons-gives you everything you need/want. I often get 2 of these.
5. Satanic: By the time you upgrade it from Dominator, you'll have godlike AS. Lifesteal is always fantastic on carries.

3d. Situational

Ghost Scepter / Ethereal blade
SnY
Maelstrom/Mjollnir /
Vanguard
Eye of Skadi [IMG]media.playdota.com/items/88/icon.JPG[/IMG]
Manta

I rarely get any of these.

1: Scepter: If you are facing physical DPS-ers.
2: Ethereal blade: Useful if gotten VERY, VERY early. Works wonders with razes. Don't get against nukers, same for above.
3: Sange and Yasha: Fallback. If you're having a hard time, comes in small components, so you can buy it even if you die too often.
4: Maelstrom/Mjollnir: The lightning is an awesome orb, you trigger it pretty often. Mjollnir's active is very useful with BKB.
5: Vanguard: If you're getting harrased too much. Get early.
6: Skadi: A very good item. Works wonders with your AS, also very good stats, but expensive.
7: Manta: I don't like illusions. Get it if you like them.

3e. Rejected

Radiance
Diffusal blade
Anything from Arcane Sanctum that isnt Hex

You simply don't need these. Not much else to say.

4.GAMEPLAY

Early game:
Go mid, unless you have a real pain of a carry that REEEEEALY needs his levels (e.g. Obsidian Destroyer), otherwise go safe lane (bot for sentinel, top for scourge)
Last hit as much as possible. If mid, creep block and deny constantly so that you can fight on your side of the river, you shouldn't risk going past the river. Farm up treads, then Lothars/Blink/BKB.

Mid game: Try to beat your lane opponent, possibly kill him with razes when he comes too close. After that, go gank isolated heroes for levels and cash. Be VERY cautious for ganks, participate in team fights but NEVER INITIATE, try to follow up with a good requiem when your enemies are below 40% hp.
Farm some more, get at least one of your luxuries.

End game: Get your luxuries, go own. Finish the game fast, unless you farm 2 butterflies and 2 more luxuries. In that case, crank up the volume and annoy your neighbors with "RAMPAGE","WICKED SICK", "ULTRA KILL", etc.

5.CLOSING WORDS

I hope this guide helps you playing Nevermore, try not to judge me for being subjective at times: i have a friend who played dota since the day it came out: he gets Mask of Madness, Mjollnir and Butterfly on a motherfucking Tiny. Subjectivism FTW.

As I said, please rate, criticize, and comment on the guide, it means a lot to me.

Credits:

Playdota.com for hosting so much information about DotA.
Icefrog for making such an awesome game.
This guide > http://www.playdota.com/guides/the-omnimage for being the best and most through guide of all Playdota, and inspiring me to write a guide myself.