What is Sylvanas motivation?

[Hellspawn]

Sylvanas was always motivated to kill Arthas, in the book it looks like she only builds up an army to kill him, develops a plague only to kill the Scourge. Now that he is dead, what drives her forward? She doesn't really care for bloodelfs anymore, she would defile their bodies without remorse as we saw in the Siege of Orgrimmar. She also doesn't care that much for her own people it seems like.
So whats drives her?

[Combatbutler]

Sylvanas was always motivated to kill Arthas, in the book it looks like she only builds up an army to kill him, develops a plague only to kill the Scourge. Now that he is dead, what drives her forward? She doesn't really care for bloodelfs anymore, she would defile their bodies without remorse as we saw in the Siege of Orgrimmar. She also doesn't care that much for her own people it seems like.
So whats drives her?

She wants to stay alive as long as possible, ot postpone her suffering in the void, so self preservation is her motivation.

[Dreknar20]

So whats drives her?

to carve out a place on Azeroth for the Forsaken

[icausewipes]

To see SW in ashes, Darn burned down, IF buried, and Exodar crumble to the ground.

[Xilurm]

She has seen what death is like. Nothing awaits her on the other side. So her goal is to live forever. And she will do anything for that. She uses her own people for that goal too.

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to carve out a place on Azeroth for the Forsaken

She could care less about the Forsaken. She only needs them to protect her.

[Maxilian]

Sylvanas was always motivated to kill Arthas, in the book it looks like she only builds up an army to kill him, develops a plague only to kill the Scourge. Now that he is dead, what drives her forward? She doesn't really care for bloodelfs anymore, she would defile their bodies without remorse as we saw in the Siege of Orgrimmar. She also doesn't care that much for her own people it seems like.
So whats drives her?

Well right now her motivations are divided:

- Self Preservation
- Making sure her people have a place in the world (can be questioned)

Until Blizzard give us more info that's what we know

[Calzaeth]

Self preservation BY improving conditions for the Forsaken.

So you can argue her methods and motivations, but the result is a better life for a race.

[Zaelsino]

Her "what joy is there in this curse" outlook had a rude awakening when she learned she was going to hell in the afterlife. She broke out with the help of the val'kyr and is now determined to live forever.

[Deleted]

She could care less about the Forsaken. She only needs them to protect her.

The Forsaken are her only way of protecting herself and remaining in the world of the living so I'd say she probably cares a great deal about them just as an extremely valuable tool rather than actual people.

Honestly, that probably means she cares more about her people than any other racial leader does.

[Lavannah]

Like everyone else has said, she's out for self-preservation. She's done some nasty things in her undead life, and she glimpsed it after throwing herself off the top of ICC at the end of Wrath in her short story. She couldn't stand knowing that there wasn't nothing for her except a void of pain and despair(even though it's what she deserves). The people she led as a ranger in life were 'nothing more than arrows in her quiver', and the Forsaken are exactly the same. It's why she's using the Val'kyr to resurrect more dead loredaerons(spelling XD) and using the inability of procreation as an excuse. She needs more 'meat shields' in a way. And once her Val'kyr dwindle down to the last one or two, she'll get desperate and turn total Lich Queen to keep on living as long as possible.

[A Dark Knight]

She could care less about the Forsaken. She only needs them to protect her.

she cares about the forsaken more than other leaders care about their people (look at varin and westfall).

Many quest in sliverpine shows that she is working so that the forsaken will make their mark on azeroth.

She turned the forsaken into this http://www.wowhead.com/quest=24982 (read q description)

[Kralljin]

She turned the forsaken into this http://www.wowhead.com/quest=24982 (read q description)

Sounds like a slightly different version of a Garrosh Forsaken type.

[Hellspawn]

If she is so self-preservish, why is she so aggressive and risks to wake the Lions(aka Stormwind Humans)?

[Combatbutler]

If she is so self-preservish, why is she so aggressive and risks to wake the Lions(aka Stormwind Humans)?

The Forsaken were already enemies with most humans in Lordaeron, Sylvanas saw a vision in which the Alliance overwhelmed and ultimately destroyed most of the forsaken. So now she took out the humans territories surrounding her and her nation, creating a puffer zone, while increasing the forsaken population with the Val'kyr.

[Scummer]

To live forever. She doesn't care for anybody else, they are simply tools that help her accomplish this goal.

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to carve out a place on Azeroth for the Forsaken

Given how she doesn't care for them this cannot be the case.

[Aquamonkey]

She doesn't really care for bloodelfs anymore, she would defile their bodies without remorse as we saw in the Siege of Orgrimmar.

That's a bit harsher than how I interpreted the dialogue. Her interaction with Lor'themar was more teasing/playful and possibly even reassuring. They did have a long history together before she died.

Prologue to Galakras:
Lor'themar: "By the Sunwell, we're getting slaughtered."
Sylvanas: "I can raise your dead, Regent Lord. Your rangers can fight again."
Lor'themar: "Sylvanas, you will leave our corpses alone, or I will deal with you here and now."
Sylvanas: "I'm sorry to see your lack of commitment."
Sylvanas: "Hrm, what about the human corpses?"
Lor'themar: "Well, I suppose that's between you and the Alliance."

Hero slain
Lor'themar Theron yells: W...where...is this blood coming from?
Lady Sylvanas Windrunner yells: I can't wait to see the look on his face when I animate his corpse. We'd better win this battle!

Lady Sylvanas Windrunner yells: I will... rise... again...
Lor'themar Theron yells: Oh my, what has overcome our dark lady?

Horde Outro:
Lor'themar Theron yells: Finally. I will never get all of this dust out of my robes.
Lady Sylvanas Windrunner yells: Oh, you're still here? I had kind of hoped you perished. You would make a very attractive corpse.
Lor'themar Theron yells: I will take that as a compliment.

[arcaneshot]

If she is so self-preservish, why is she so aggressive and risks to wake the Lions(aka Stormwind Humans)?

Probably because securing your kingdom's borders is a sovereign right and securing said borders makes Sylvanas feel more safe.

Not to mention if Stormwind wants Lordaeron that bad they're free to take it by force of arms, but since they're not able to secure a foothold in Forsaken territory in more than one location taking Lordaeron isn't going to be as simple as it could've been when Sylvanas didn't care as much.

She could care less about the Forsaken. She only needs them to protect her.

People keep saying this without being able to interpret that making the Forsaken stronger makes Sylvanas more safe, therefore the well being of the Forsaken is clearly on her mind.

[Deleted]

That's a bit harsher than how I interpreted the dialogue. Her interaction with Lor'themar was more teasing/playful and possibly even reassuring. They did have a long history together before she died.

Lor'themar: "By the Sunwell, we're getting slaughtered."
Sylvanas: "I can raise your dead, Regent Lord. Your rangers can fight again."
Lor'themar: "Sylvanas, you will leave our corpses alone, or I will deal with you here and now."
Sylvanas: "I'm sorry to see your lack of commitment."
Sylvanas: "Hrm, what about the human corpses?"
Lor'themar: "Well, I suppose that's between you and the Alliance."

Lor'themar Theron yells: Finally. I will never get all of this dust out of my robes.
Lady Sylvanas Windrunner yells: Oh, you're still here? I had kind of hoped you perished. You would make a very attractive corpse.
Lor'themar Theron yells: I will take that as a compliment.

Hero slain
Lor'themar Theron yells: W...where...is this blood coming from?
Lady Sylvanas Windrunner yells: I can't wait to see the look on his face when I animate his corpse. We'd better win this battle!

Lady Sylvanas Windrunner yells: I will... rise... again...
Lor'themar Theron yells: Oh my, what has overcome our dark lady?

Did they cut that particular exchange? Sylvanas offering to raise undead Blood Elves and Lor'themar getting all upset I mean. I've seen it posted around but I don't recall hearing it in SoO.

[Aquamonkey]

Did they cut that particular exchange? Sylvanas offering to raise undead Blood Elves and Lor'themar getting all upset I mean. I've seen it posted around but I don't recall hearing it in SoO.

It's in the prologue to Galakras.

[Zaelsino]

Did they cut that particular exchange? Sylvanas offering to raise undead Blood Elves and Lor'themar getting all upset I mean. I've seen it posted around but I don't recall hearing it in SoO.

Pretty sure they cut the part where she starts cackling like a madwoman and summons the val'kyr to "sow terror in the streets of Orgrimmar" or somesuch.