I'm a level 43 hunter trying to solo this quest, and always die on the final boss. I usually get him down to 9k health (lowest at 5k), but by that time he has at least 5 hardened barks going (don't know if they stack) and he heals. And by the time he has all those hardened barks, I can't do enough damage to keep his health down. Tried about 8 times now, and starting to get a little frustrated. Any ideas?