I'm just using reptile carpet for them. I did have a mouse bite my butter when I first got that one like 5 years ago. Bit him right on his neck and left a nasty cut. Ever since then I always stun them first and watch for any bites. If it bit him in the mouth somehow then I may have missed it. Yes this didn't seem like typical mouth rot or typical RI. That's why i wanted to know if anyone has seen something like this before. Like the little spot on the gums COULD maybe be rot but then why would the whole face be puffy? Wouldn't only the spot where the puss is be inflamed? I have worked at a pet store for almost 8 years and have been into snakes for even longer than that and I have never seen this before. And he ate like 3 or 4 days before I noticed the neck.