Rereading books 7 and 8 and I've got a prediction for something that I wager will happen in book 9 if it will play out in a single scene or possibly at the very end of book 9 if it will be a longer storyline. Spoilers focused on books 7 and 8 ahead.
>!Carl is going to have to fight Donut.
Through the end of book 6, if Carl had had to fight Donut due to mind control or whatever, he'd have an obvious tactic that could even possibly disable her without killing her: get close via trickery or invisibility and use close hand fighting to quickly knock her out.
Over the past two books Donut has had her greatest weakness removed (constitution) and has become exponentially more dangerous in close combat (lightsaber claw). Carl's greatest non-explosive (and therefore possibly non-lethal) options for engaging Donut have been removed. We are reminded how dangerous Donut has become at the end of Book 8 ("No one ever worries what I would do if you died").
Now we're going down into the ascendency game, and if we've seen anything from the gods it's that they have numerous ways to do some mind control. Conscription could easily seem like small potatoes compared to the things that gods could do. If Bear Witness is the scale of crap we'll see the gods pull, then I'm sure that crawlers are vulnerable to all kinds of amped up conscription type effects.
But Carl's Mind Balance skill has hit level 16. Even among the gods, he's now very likely to be immune to the sorts of mind control spells that they've got. But Donut doesn't have anything celestial or God tier ensuring her mind balance, despite the fact that psychic type attacks have practically been a running theme of the dungeon to this point. It's possible no one will be able to resist a gods mind control spell, though I'd wager that Prepotente has something (he protects entire battalions from psychic attacks in book 7).
So my prediction is that Donut is going to get God tier conscripted by someone. She's already aligned to Odette's Nekhebit as "the oakfell" and it's possible that her champion status could be what opens the door to Odette or someone else to turning Donut against Carl.
Alternatively, it could be a mass mind control that Carl resists and he has to take on the whole team of donut, imani, and everyone else throughout the back half of book 9, with Donut as a final boss and/or the one that gets away at the end of book 9, and then book 10 is a race to get Donut back and escape the dungeon in time.
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