"Isn't the mind the part that would make us different?"

"I'm not planning to give you psychoactive drugs. Checking drug reactions on mindless twoleg bodies works fine."

". . . Okay, if you say so."

Cam makes a basement dweller Cinderpelt and demonstrates the intended operation, then checks for any of the listed side effects.

It looks fine.

"What the fuck?" meows Princess, spotting the doppelganger and snapping out of her purrreverie.

"Uh, I'm showing Cinderpelt how I'd swap out her leg. On this unthinking physical copy."

She glances over at the forest dweller Cinderpelt, who isn't objecting to this process.  "Oh.  Okay.  Neat."

"That looks fine to me," declares Cinderpelt, lying down in a similar position to the basement dweller.  "Go ahead."

"Lidocaine going now, let me know when it stops feeling burny."

"Now, I suppose?"  She watches her leg.

He pinch-tests a toebean. "Working okay? - basement dwellers don't respond to pain, I can tell it's not having an allergic reaction but I don't know if it's doing its job."

"I felt that?"

"...oh dear. Okay. Uh, I can try a higher dose, I can try a sedative, I can make you some poppyseeds, I can try just doing it real fast..."

"How likely are you to make a mistake doing it fast?"

"Not particularly, if you hold very still."

"It twitches sometimes already . . ."  She sighs.  "Probably I should take at least a few poppy seeds.  And a stick to bite on."

Cam makes some poppy seeds and a stick for her. "Still want to go through with it?"

She separates a few seeds out and cronches them.  "Yes of course.  Just give me a moment for these to take effect."

It's not very long at all before she takes the stick in her mouth and mews assent around it.

"Okay. Three, two, one -" Leg goes, leg appears.

Cinderpelt braces herself, but not in a way where she doesn't hold her leg very still.  Once he's done, she spits out the stick and starts on investigating her new limb.  "Oh, that wasn't bad at all.  Almost didn't have time to hurt."

"I do my best!" He tosses the discard leg onto the basement dweller. "Okay if I burn these? I won't let it spread."

Fireheart goes through several very different illegible cat facial expressions in a very short span.  "That's fine," he mews, mildly, when the other two Clan cats look to him.

Assorted cat parts are instantly immolated; a ring of cold contains the flames.

Cinderpelt tries standing up, walking, and - if that goes well - running?

Her new leg should work good as new modulo some lidocaine!