The longest fight I ever had was against Mehrunes Dagon. I had plenty of health potions, so I pushed the attack. I ran up, hacked, and then... :wallbash:. I think you get the idea. So, on my second attempt I enabled god mode. I spent near 40 minutes hacking away at him before I decided to check online to see how much health he started with. It was then that I realized you aren't supposed to attack him. :whistling: