In the Main quest line, you get to the Valley of Blades, and you have to protect the ancestral tomb, where several named undead are spawned that you have to kill. The first one is Divad Hunding. He seems to be respawning every so often. I am a healer so I don't really cause any damage, and as such these fights take FOREVER. So Divad is the first one you kill, then there's another, and then during the next fight you are fighting 2 of them and he respawned during that. So I killed him again, and then had to fight the 3 at one time. After killing 2 of them, the 3rd reset which was frustrating, and by the time we killed him then Divad had respawned AGAIN, and at that point I ended up dying. It's bad enough that it takes so long to kill all these guys being that I'm a healer and these are solo quests....but you'd figure none of these guys should be respawning at all!