First, my game is patched to the latest.
Immediately upon starting the fight I'm hit with something that does over 500 damage per second. I've reloaded nearly 20 times now and no amount of jumping or skill usage avoids it. Using the shield does nothing, and no potion I have (Ok, I have one crappy potion because I'm a moron for not being prepared) can keep up with the ticking damage. The autosave outside the arena is pretty much useless since the way back is blocked. The closest save I have is 2 levels ago.
What can I do here?
edit: Just tried it 10 more times. It looks like some sort of missile as I don't see any effect on the ground, but no amount rolling or dodging can avoid it. It takes me from 950 HPs to 0 in 1 second.