As I was in the Boiling Fields of Vigrid Roughland, I was on one of my many adventures. This adventure involved the quest of taking out Lothin Doombringer. After I had knocked him down to 141 hit points, I used my trusty sword provided by Valeska Redwind and inflicted 142 hit points of damage.
Instead of killing him, it went through another round of him being at -1 hit points. His picture disappeared as if he died but he was still able to cast a spell and damage me. It took the next round for him to be taken out.
Don't know if this was intentional but this may happen on any creature you reduce down to -1 hit points. Can't say it will but if this happened on this one.
Not unique to that monster, it happens all over the spiral, boss and nonboss alike. They will crawl back from -1 gaining a point or two each round until their image comes back, still gaining pips, and still fighting you.
I'd like to add to ElFuego's post and say that this is not exclusive to Bosses. This happens for every combatant on the field. At the beginning of most every round, before you pick your cards, you will notice your health go up by 1-3 points. I consider it "natural healing". If this happens directly after you have (excuse the phrase) "barely" defeated a boss or mob then they ALSO are awarded 1-3 points of health and are automagicly alive again. So make sure that your final blow will take them well below the -2 health range or you may find them popping back up out of the grave like the ghoul does. lol.
I think it's called the Eye of Truth. Without checking my Quests, I can't remember for sure, and I don't have W101 running right now.
But has anyone did this quest, just to get to the last of four battle chambers just to fight, after that fourth fight ... nothing?
And your Quest Arrow is telling you that you are standing right on top of it?
I hope this gets fixed before I go back in there, if it hasn't already. It was a pain, but I managed to solo it, just to be denied my "cookie" at the end of the fight. And a friend who ported in to help me search found nothing either.