So, this being my first written guide, I have to say that you should take everything you read here with a grain of salt. All of this is made from my personal experience with Sylvanas and how I like to play her.
Have fun reading up on Sylvanas Windrunner and please remember to vote if you have enjoyed your read and tested this build for yourself!

Ner'zhul loses control of the Banshee's minds, and Sylvanas as well as a group of Banshees break free of their control. Because of this, a group of Dreadlords approaches Sylvanas and demands that she assists them take control of Lordaeron which she to begin with, agrees to do. It was pretty much a plot to get rid of Arthas, Dreadlords are a bunch of backstabbers. They arrange a ambush on Arthas which fails. Since she was the leader of the Banshees splinter cell ( thus the title Banshee Queen ), a group of Sylvanas' Banshees still disguised as loyal to Arthas lures him away from the failed ambush and kills his bodyguards, meanwhile Sylvanas manages to find and possess her body which she uses to take a shot at Arthas with a specialized arrow which paralyzes him but refused to end him quickly as she wanted him to suffer as much as she had. But Kel'Thuzad arrived and intervenes. Sylvanas goes on to join the Horde out of necessity, she knows very well that the Alliance would never willingly accept the forsaken, the undead into their ranks. Later, she convinces Thrall to allow the Sin'Dorei to join the Horde, she however knows that she can never really return to Silvermoon as she is right now. After the Pandaria campaign has found its conclusion, Sylvanas takes part in the hearing of Garrosh Hellscream, former Warchief of the Horde. There she meets her very sister, Vereesa Windrunner and two begin to bond together. They meet at Windrunner Spire in the Ghostlands and cleanse it of the undead scourge that has been pestering it and begin to plot how to kill Garrosh. Neither of the Windrunners would let him see the light of day again. That is, until an unfortunate event has turned the tables for the former Warchief, out of pure grief, out of pure hatred, there was just one thing left for Sylvanas.. VENGEANCE

Sylvanas Windrunner is a Ranged Specialist, her speciality is to keep lanes clean and deal enormous damage to both buildings and enemy heroes, she can also easily clear mercenary camps.

Black Arrows (TRAIT)
Attacks and Abilities stun Minions, Mercenaries, and Towers.

Withering Fire
Shoot the closest Enemy for 25 damage, preferring Heroes.
Stores 5 Charges.
Gain 1 charge on nearby enemy Minion or Mercenary deaths, and 3 charges on nearby enemy Hero Deaths.
Mana Cost: None.
Cooldown: 2 seconds.

Shadow Dagger
Deals 10 damage and an additional 40 damage over 2 seconds to target unit. The effect spreads to nearby targets.
Mana Cost: 75 Mana
Cooldown: 10 Seconds.

Withering Fire
Sends forth a wave of banshees dealing 30 damage to all targets. Reactivate to teleport to banshees' location.
Mana Cost: 75 Mana
Cooldown: 11 seconds.

Wailing Arrow (Heroic Ability 1)
Shoot an arrow that explodes for 200 damage and silences enemies for 2.5 seconds. Can be reactivated to detonate the arrow early.
Mana Cost: 100 Mana
Cooldown: 90 seconds.

Possession (Heroic Ability 2)
Force an enemy Minion to fight for you. It gains 20% Attack Damage and Health. Cooldown increased to 20 seconds when used on Catapults.
Mana Cost: 20 Mana
Cooldown: 4 seconds.

With the Wind (Good Choice!)So, this is something that I have used the very first time I have played Sylvanas. This ability then easily exceeds her actual range and if you go for talents such as then you can actually kite melee heroes. Though Heroes such as Kerrigan and Zeratul have an easy time catching up to you.
Barbed Shot (Optional Choice!) This ability was fun to meddle with at the beginning, but through further playtesting I have found out that it is not that great. You can push extremely well with it at a good pace, outshining heroes such as Zagara and being on par with Sgt. Hammer. But it does not pay off for teamfights.
Corruption (Optional Choice)Given you have a team to back this choice up, I could safely say that you can rid towers very quickly of their ammunition and bother 1-2 lanes at the same time like that. However, you can also keep buildings stunned, so this is not a very good choice either.
Lost Soul (Negative Choice)Having played with Sylvanas, I really cannot recommend this. 2 seconds cooldown reduction on a single spell versus a range increase or flat damage increase on your is not favourable.

Envenom (Good Choice!)This is the top choice. You can pair it together with your DoT effect from to make a powerful finisher that can possibly only be outhealed. This is the main choice on many Assassin heroes because of it's damage on demand.
Ranger's Ambush (Optional Choice)Given you want to play aggressive or simply want to push lanes harder, this is still a relatively alright choice, which however does not outshine
Paralysis (Negative Choice)I cannot see the use yet for a 1 second duration increase to your trait.
Overflowing Quiver (Negative Choice)It just does not add up compared to the other talents. I have tried it out one time and I really felt like I missed out on a whole talent, which is not alright.

Life Drain (Good Choice!)After proper playtesting, this ability outshines the others. You require that heal because you might just face that annoying Raynor or Assassin with a healer that you need to keep up with.
Unstable Poison (Optional Choice)Unlike his ugly brother , this ability is actually incredibly useful! You can clear waves faster than and that is saying a lot. One triggered explosion is enough usually to clear the whole wave. And it also helps in teamfights when enemies are bundled up together.
Shade Form(Negative Choice)While I like the idea of a stealthy escape mechanism, cant say it is as useful.
Follow Through (Negative Choice)You are an ability spammer, so at first you might think that this is great because your auto attacks will do 25% more damage than usual then, right? That's true. But the clearing power is still superior.
Mercenary Lord (Negative Choice)I have been sad panda ever since this ability has been nerfed. It was a serious contestant since you could just leave the lane to the mercs. While it is still a great damage increase, you would require your team to back it up.

Wailing Arrow (Good Choice!)This ability really is your so called only choice here. A silence in itself is a very strong tool. If i am not mistaken, it allows you to cancel 's ultimate for example while it does deal a lot of AOE damage and can be applied to multiple heroes at the same time.
Possession (Negative Choice)I do like the idea, I really do. I just do not like the fact that this ability does not work on mercenaries from the get go even though it is an Ultimate. Therefor, it is the inferior choice for me.

Evasive Fire (Good Choice!)Playtested the second build a lot and I have to say that I prefer this talent largely over the others. It will give you the burst of speed that you need when you are chased or chasing. (but do not chase too far, remember that)
Splinter Shot (Optional Choice) Your deals a lot of damage on its own to a single hero. Being able to target 2 heroes or 2 minions (which enables you to easily snooze-solo Bruisers!) is just too good to pass up on!
Spell Shield (Optional Choice)If you are absolutely sure the enemy team is going to target you every single time with heavy magical damage nukes, then go for it. No one will hate you for surviving teamfights longer than 1 second.
Overwhelming Affliction (Optional Choice)Given you are facing a hero such as Kerrigan that you just have to get away from, then this could be the choice. But you do have an escape mechanism and do not need to rely on kiting as much as other heroes.

Blood for Blood (Good Choice!)Facing that tanky hero such as Diablo or simply taking the air out of Illidan is such fun, you just cannot pass up on it!
Cold Embrace (Optional Choice)While this ability works really well together if you are setting up some burst, it sadly does not outshine all other talents, but poses a viable optional choice.
Will of the Forsaken (Optional Choice)I have not playtested this ability yet because my positioning is usually good enough to avoid being influenced by heavy crowd control. But I do believe that this is an activation mini-sprint that breaks through snares and stuns. Which makes it a reliable optional choice.
Windrunner (Optional Choice)The only reason I have not put this as a negative choice is that you can actually make fun plays with this talent. Not only can you double the damage of your but you can also confuse the enemy with it. But I do however not recommend it over any of the other abilities.

Deafening Blast (Good Choice!)Given you are assured of your position and you are satisfied with how your team works, you can go for the full damage build. THis is a great talent if you manage to land the center on several heroes. A five second silence and a additional 50% damage on your nuke is just that cherry on top of the metaphorical Megakill.
Bolt of the Storm (Good Choice!)You may have an escape already in your ability, but the wave requires time to travel and sometimes, you just do not have that time. If you just know you need to stay alive for your team and you are sure you will be targeted, take this instead of all the other final talents.
Dark Lady's Call (Optional Choice)We have not chosen this talent in this guide. So you will not be able to use it. It will however allow you to turn the game a bit around by messing with the mercenaries of the enemy team, finally!
Fury of the Storm (Negative Choice)You are dealing enough damage as it is to creeps and mercenaries. This is not as desirable as the damage increase on your ultimate or .

I did have a few requests to explain on how to use haunting wave to it's most efficient factor. And no, none of this will require you to skill anything else. This is all based on the purely un-talented haunting wave.

Haunting wave is a relatively slow wave that progresses on an about 1.0-1.5 second window of opportunity, much unlike Zeratul's blink, it is not instant but it will render you invulnerable!

The invulnerability given by haunting wave is something that I have been toying around with ever since Sylvanas has been released. She is an amazing hero and I really hope they will not take this out after I write all of this.

We all love and know Nova's triple tap ultimate. we really, really hate it though. That is why, when you face a nova that tries to snipe you on long range, you can just start your haunting wave and immediately travel to it's next point to cancel Nova's ultimate. Now, I have never been on the "Receiving end" of a Sylvanas cancelling my like that, but I believe it will at least cause the ability to go on a 10 second cooldown like most heroic abilities.

Mind Games
When you are using Haunting wave, always watch your enemy. Do they start chasing your wave? Or do they keep chasing you? Is a team mate of theirs ready to intercept you should you go to your wave? Watch all of that when you use it. I know it is a lot to take in, but it gives you that little advantage.

When you are actively using Haunting Wave to escape, always go in a directly different direction from where you have shot the wave. Using the window of opportunity, you can not only confuse your enemy, but also create a much greater distance between your enemy and yourself.

You cannot use haunting wave, even if it is already flying, while you are rooted. So a good Thrall will wait to root you until you use your haunting wave. Be on the lookout for that.

First of, thank you all so very much for reading this far into the guide. I would very much like to encourage you to give me feedback and if I have explained anything wrong, please feel free to correct me!

This is a first, somewhat raw interpretation of my very first guide. So if you have any ideas of what I could add to make it any better, please do speak up!

Please tell me how the game works out with build 1# or 2#, they are very different and I suggest you test them in quick matches before you jump in to hero league.

Made it to rank 5 so far using frequently Sylvanas in Hero League