[dremora]

Just going to say, if you got hit by 400 mechanically, you would not recover. You would have dropped below -10 and been struck dead on the spot like Silus had been by a IGMS. I think you either saw it wrong or it was a graphics glitch or a mix of numbers as both of you hit eachother resulting in your attack damage having a 0 on the end of a crit for 40. Are you sure you were not injured below max health before this happened?

P.S please repost in correct format as priority over replying to this, its simply just a thought on what may have happened