The idea for this story is from Barbacar, check out their stories. It's one of those what ifs of weirdmaggedon.

Struggle? There was none. There couldn't be. They'd given their struggle and had nothing left. They'd fought hard but the fight was over. Cipher had won. They'd done everything in their power. Everything in everyone's power. Even a whole town of weird couldn't fend off a world of weirder. Was it fair? Of course not. Bill Cipher didn't know the meaning of fair and never would. He stood there with an ominous gleam in his eyes, blinking, deciding their fate with obvious glee.

Dipper?

Mabel?

Dipper?

Mabel?

Who would die first? That was the only thing on his mind.

The victims had a lot more on there minds than that. They squirmed and struggled and then just stared as they prepared for their petty meaningless lives to come to an end.

No. Wait, no. It wasn't meaningless. Mabel glanced at her brother and tried not to cry. It definitely wasn't meaningless. Her life had meaning because she had family. She'd had the best summer of her life with that family. Had grown attached and fallen in love with the town and what mattered. She and her brother had shared everything, done everything together. Been best friends since they were born. Argued, laughed, cried, suffered. He was her family. And that would be forever what mattered. What was worth living for.

And... And what was worth dying for.

"Bill! Take me! Let my brother go!" She bellowed. The light settled on the shooting star symbol and he grinned psychotically.

"My pleasure shooting star. The pine tree can go-" Dipper looked at her, shaking his head violently-

"Wait! I surrender." Suddenly both of them were dropped to the ground with a thud, terrified, but fine for the most part. Dipper looked at Mabel strangely, as if shocked and more than a little frightened. Their whole family was making sacrifices to save each other. To save family, the only thing that mattered.

Dipper cautiously reached for her hand and squeezed it as she tried not to cry again. Their Uncle had just given himself up. A few seconds ago Mabel would have done the same. Even now she knew that no one was going to get her brother, no matter what. Not if she could stop them.

Not if she could take his place.

They'd lived their whole lives together.

But if she had any say, they would not be dying together. Not now, not ever.