I once made a encounter featuring a human that was in fact a humanoid, as the encounter went. I had him flee from a surprise round in order to get a better position from the players. But during that scene, the human was shot by one of the heroes in the back. And with the humanoid having immunity from physical damage, I made it so that the wound was instantly healed after the hit (dealing 0 damage to the human).
Later throughout the encounter he transformed into his werewolf form and fought against the heroes. But sadly it was a fast fight for me (the DM), and he found himself beaten. (The heroes had magical items and/or a way to attack in a magical manner.)
He was then healed (1 hitpoint) in order to talk to the players. At the end of the interrogations, one of the players chose to knock him out (not kill him) by punching him in the face… And I said that he gave him a good swing of his fist and hit him hard in the face, which turned out to be effectless (due to his immunity).
Now here is my question… Was this stupid of my part? Do Were-creatures only have their immunity powers in their hybrid- and wolf form? (I mean, I think it was funny somehow.)
I remember reading into the book about this, but I couldn't find anything specific.
(I believe that the beginning of the encounter made for a very interesting start by showing that a human had [for some reasons] regenerative powers, but in the end of the encounter it was used as a joke.)