I thought that when you get defeated in a dungeon and return right away you only have to fight the ones that were alive at your departure. So what's up with fighting Bellows. I got defeated and when I got back up there (immediately!) all 3 of them were alive again. Was I dreaming about the dead ones remaining dead ?
In these type of Dungeons, if you re-enter like 30 minutes after you leave I think is the time you have to get back, it does not reset every battle that you have finished. If you for example get half way through a battle, and then die, you don't have to do any battles before that battle, but you will have to start the battle that you were in the middle of again. But beware, if you decide you want a friend to go help you with the remaining battle(s), the dungeon WILL reset, because your friend(s) did not do the work that you did before. Also if you are in with more than one person and you flee, you have to port back to your friends in order to pick up the dungeon where you left off. Going through the front door will make you start the dungeon over. Hope this helps! :-)