"...yeah, probably." 

"Were there any other physical alterations than the obvious ones?" he asks, making Fëanáro's wings and ears tingle very slightly.

"...I can control my heartrate and stuff by thinking about it? ...actually I should check if I can control my nerves directly too, I haven't tried that yet."

"Fascinating. And I think I got a bead on your speech muscles."

"Okay. Try the oath thing first, then we can see what happens if I try the body control thing."

He moves his fingers again, and Fëanáro finds himself saying the oath. It feels very strange, his muscles move in weird ways that don't quite hurt but aren't natural, either, and it sounds a bit slurred but perfectly comprehensible.

And it counts, relevantly. "That worked. Escape clause."

"Interesting. I wonder why that worked to create an oath when there was no intention but the intention was relevant for raising your arm."

"Oaths create - a psychological compulsion to do or not do the thing? So if you're bypassing that then you can move me or whatever. Can you try again while I tamper with the bodily control thing -"

"Yes. Tell me when."

"Go."

He goes.

And what happens if he tries to take his nerves back - nothing - what happens if he cuts off blood flow to his arms -

That screws with the cape. He tries sending commands to the nerves but they don't seem to have enough juice to make the muscles go. "Interesting. What did you do?"

"Cut off blood flow to my arm." It's turning blue.

"—you should probably not do that."

He stops. "But it's good to know I can."

"Yes. You'd... probably have to do it with your tongue, to prevent swearing oaths."

"Worth it."

"Depending on how absolute these oaths can be, yes."

"...I possibly shouldn't tell people this? But very absolute."

He nods. "Is there anything else you would like me to test?"

"I think that's all, thanks."

"You're quite welcome!" He stands up and leaves.

The next master is someone whose costume is very colourful—specifically, blue and red, clashing and swirling into each other. "Hello."

"Hi."