Alternate Mabel Pines

This is a list of alternate fates for Mabel Pines from Gravity Falls.

Tourist Trapped
First of all, what it would be like for the rest of the characters if Mabel had been captured and made queen of the gnomes: assuming Dipper just let the zombie thing go, when she goes off one day with "Norman" and never comes back, Dipper would probably assume the zombie killed her, and beat himself up over it, maybe to the point of suicide. Stan would go into drunk mode, so he wouldn't have to feel bad about it, which he really would. If that's not terrible enough, meanwhile Mabel is the gnome queen, getting raped by gnomes and having gnome-kids for all 1,000 of them when she's 12 years old.

Legend of the Gobblewonker
If she and Dipper won the monster contest, she would spend her life eating garbage in a hamster ball. There's not much else to say about this.

The Inconveniencing
If Dipper hadn't admitted his not being a teenager, the ghosts might have stayed in her body forever, and depending on how possesing someone works, that either means that she's unconscious inside, or eternally screaming and begging freedom. And the teens would stay in the store forever, hiding from her.

The Time Traveler's Pig
Assuming she just keeps banging her head against that pole for months, and then stops eating, (from the second-to -last reality) she would probably starve to death or die of thirst.