He licked his wounds obsessively, as if sure they would heal that way, unaware that most of the time he was making things worse. His master yelled at him, told him to stop, but he had to do something, couldn’t let them fester.
He would sneak away at times to work on his damaged legs and tail. If he found other members of the pack with wounds he would help them too. No harm in trying. If he could, he would gladly heal the world.
Impossible perhaps, but keep going and you never know.