There is a issue with fighting the bat in Empyrea. If you flee and use the dungeon recall you just port back to were you fled to. I have fought this battle on several wizards now and on multiple accounts. The outcome is the same. It is definitely a bug. Thankfully since I was in the dungeon with others on my friends list I was able to rejoin by porting back to them instead. I don't foresee others being as lucky if they used the team up option.