If you look at the troll's card for the miniature game you'll note that he has a single check box next to his feral regeneration ability, which I believe means he can only use it once. I suspect that this is all a miniatures thing too.
Gloombunny said:I didn't get any impression like that. I thought the gradual petrification thing meant that the attack has to be used multiple times to fully statue-ize someone.