My current WIP is a prehistoric fantasy novel which is about a hunter-gatherer woman who must rescue her sister from a tribe that wishes to sacrifice her to their volcano god. This other tribe is a separate species of hominin whom the protagonist and other humans (as in Homo sapiens) of the setting refer to as "mountain-dwellers". They're physically stronger and stockier than humans, but have simpler technology and have a level of intellect comparable to that of our world's Neanderthals and Denisovans.
Anyway, the reason these mountain-dwellers are able to track down the heroine's sister and capture her is because they have a human helping them, namely the heroine's ex-lover whom I would consider the real villain of the story. This guy got himself kicked out of the heroine's band after he tried to force himself onto her, but like many ex-boyfriends, he still wants to claim her as his mate. His plan is to use the heroine's sister as a bargaining chip, letting the mountain-dwellers throw her into the volcano if the heroine doesn't agree to let him back into her life.
And this is where I'm a little stuck. The mountain-dwellers he's helping want to sacrifice the sister to the volcano, believing that it'll prevent the next upcoming eruption. If our villain offers to have the sister spared as long as the heroine agrees to become his lover again, that would piss off his mountain-dweller allies. Admittedly, it wouldn't be out of character for this dude to betray the mountain-dwellers, but I'd like for him to have a backup plan should the heroine agree to his demands (which would require him to call off the sacrifice of her sister). What could that be?
Anyway, the reason these mountain-dwellers are able to track down the heroine's sister and capture her is because they have a human helping them, namely the heroine's ex-lover whom I would consider the real villain of the story. This guy got himself kicked out of the heroine's band after he tried to force himself onto her, but like many ex-boyfriends, he still wants to claim her as his mate. His plan is to use the heroine's sister as a bargaining chip, letting the mountain-dwellers throw her into the volcano if the heroine doesn't agree to let him back into her life.
And this is where I'm a little stuck. The mountain-dwellers he's helping want to sacrifice the sister to the volcano, believing that it'll prevent the next upcoming eruption. If our villain offers to have the sister spared as long as the heroine agrees to become his lover again, that would piss off his mountain-dweller allies. Admittedly, it wouldn't be out of character for this dude to betray the mountain-dwellers, but I'd like for him to have a backup plan should the heroine agree to his demands (which would require him to call off the sacrifice of her sister). What could that be?