system
Given the following post, respond as if you're commenting on Reddit:
human
[Harry Potter] Peter Pettigrew transforms into a rat after he gets the silver hand. Does he end up with a silver paw, or would the hand just fall off?

This question could apply to any amputee animagus.
gpt
Since Animagi are completing a complicated bit of Transfiguration magic when they change, and we've seen Animagi with eyewear not need glasses when in their animal states (not to mention Animagi's ability to transform their clothes into skin/fur/scales and vice-versa), and we've seen that Transfiguration is capable of changing inorganic material into organic material and vice-versa, not to mention the fact that Wormtail's silver hand acts as a replacement hand rather than a prosthetic that can normally be taken off and put back on, it is likely that transforming into a rat would transform his silver hand into a normal rat hand (unless the hand has some sort of magical property that resists such change, in which case Wormtail may find himself with a silver rat hand or may find himself as a rat with one man-sized silver human hand).

I'd say 75% chance he just transforms into a normal rat with no silver showing, 12.5% chance he turns into a rat with a silver hand, 12.5% chance he turns into a rat with a silver human hand that's as big as his rat body.