Here's a What If for you: Instead of Tara dying because of Warren's madness, what if it was Dawn?

Must Haves:
 
1. Dawn dies in front of Buffy in the yard by Warren's temper tantrum. Due to Buffy's injuries from patrol, she's a little too slow to save Dawn. Bonus points for Dawn saying something to Buffy that's meaningful (could be anything from "I love you", to her being happy to be the one saving BUFFY for a change)

 2. Buffy goes DARK. She's been hurt, and the only she cares about is killing the author of her pain. She has to kill Warren in a way as bad or worse than what Willow did to him in canon. Whether she manages to kill the other two idiots is up to you, as well as whether she tries to destroy the world.

3. When her friends nearly stop her the first time, she reaches deep and accesses the Primal side of herself; the result is she gains ALOT of Power. The reason she gets this power could be the result of a spell she gets cast for her, or it could be the consequence of her resurrection making her something more than a Slayer. It could even be the result of Buffy actually Slaying Glory instead of Glory hiding in Ben. However it's doe, she's the equal of Canon Darth Willow.
 
4. Spike (or Spike/Tara if you're feeling up to an eventual threesome pairing in any possible Sequels) is the only one(s) to be able to stop Buffy at the end. Whether victory entails a super-smackdown or a Xander type saving the world, or something else altogether is up to you.

5. Buffy's tapping of her power the way she did carrying permanent effects. These effects will require Buffy to leave Sunnydale at least for a while in an attempt to understand and master what she has/is becoming.
 
Optional (please pick at least two):
 
1. Angel showing up with his crew to try and help due to Cordelia having a vision of Dawn's death and Buffy's reaction. Bonus points for Buffy handing them a smackdown. More bonus points for having Faith and Cordelia getting Visions and Dreams of the sheer scope of the potenial disaster.

2. Buffy needing to 'power up' in a way similar to what Willow did in canon. The result should result in the death of at least three beings that are not scoobies. The beings can be some of the more powerful demons, sorcerers, or both. Major Bonus points for Giles pulling the same trick on Buffy that he did on Willow, trick her into trying to drain him, and feeding her energy that links her to everything.
 
3. Buffy's recovery including a stay with the Coven; MAJOR bonus points for Spike or Spike/Tara going as well, both to learn things themselves as well as to help keep Buffy stable.
 
4. Faith being given a shot at proving she's gotten back on track. Bonus points for Faith maybe saying or doing something that helps Buffy start to come to terms with what has happened (After all, Faith's been on the dark side of things, could give insight that you can only get by having been there yourself).

 Please note, I am usually open to tweaks on my challenges, especially if the one who tweaks involves me in the discussion, so I have some Idea of what's going on (I LOVE the process of Brainstorming as much as I love reading!)