"So how would we be getting her out...?"

"Yes, but I notice her power was supposed to be 'I win' and she did not win."

"Because the entity messed with her power before they killed it. Couldn't be infallible against entities or Endbringers. You can copy the version from before that."

"I also notice that her power was supposed to be 'I win' but did not turn out to be 'I make my attempt to win in a remotely ethically palatable way' and I am not sure to what extent she was able to tweak that and simply didn't bother."

"I could if I knew where to put them. Is it the same place the passengers wind up? That one I seem to have divined by copying alone."

"No, they throw those across who knows how many dimensions. Finding this one is going to take a bit of cheating."

"Okay. So I can Butcher myself a Contessa, see if she thinks I need any extras - do you happen to Thinker yourself the information of whether I can do this multiple times or if I ought to load up a single Butcher with a lot of stuff, Tattletale? - use that to see if Kithabel can be got out and even if she can't use it to aim black holes."

"No one ever has multiple, so there's no telling what would happen if you tried. The other thing is that copying someone's passenger wouldn't be the same as copying their power. A lot depends on the individual and the trigger event. Wait, you can't conjure yourself a trigger event at all. Guess it'll have to be a vial."

"What if those aren't working anymore?"

"Then we have a problem. Theoretically you could copy the extra brain bits someone had post-trigger, not just the connection, and just see what it does when it's attached to your head instead of theirs. But past a certain point it'd be less risky to use two six five on Labyrinth."

Then the thing to look at is the catalog Cauldron showed their customers. Those ones have already been tested, and are conveniently ranked by interestingness and power of the result as well as by reliability of the vial.

And what is the least interesting most reliable vial?

A sample they called Balance. The name might be familiar from elsewhere in Cauldron's more secret notes, as they took to diluting other formulas with this to make mutations less likely. When taken by itself, the Balance formula gave remarkably unremarkable powers: marginal improvement at picking up skills, or an appearance that gradually shifts to fit the subject's current idea of really good looking. The theme seems to be that it makes the recipient a better example of what they would want to be along some axis. It's a drinker-friendly vial, if low power by cape standards.

"You remembered it! Normally people forget that right away. I'd grill you on it, but it's not a priority right now."

"Well, that's promising, in a way. Right. I will make a jailbroken Contessa and see if the shard does anything horrifying and if it doesn't, Butcher next."

"Better make sure she's restrained and gagged at first. If the thing you make gets piloted by a violence-prone passenger, I'd rather not have to fight it."

"I do not know any doomsday devices, because I have never anticipated the need to wreck a planet I couldn't be within a reasonable astronomical distance of. You want the two six five jailbroken?"