"Hmmm." Papyrus considers the half-attached bone, and guides it with his other hand into seeming to move around. It's connecting just enough not to fall off, but it's not tethered to his soul in whatever way makes a bone part of him.

"If I knew how to make a basic bone that connected, maybe I could make another skull... But, that's scary, too. What if it started thinking for itself, instead of being an extension of me, and then I had to dismiss it...? Unless."

They've already seen exactly that, haven't they?

"Sans' blasters became their own creatures, sort of. Maybe, if I ask him how he did that..."