Pretty sure I tried at all level other than Sire. When I tried, I did not have the option to feed at all. And as far as I can tell no one was carrying garlic Is there a way to incapacitate an essential NPC for a period of time (maybe 48 hours) if they are drained dry? That way if you feed on them to the point where they would normally die, they would stay sleeping/incapacitated for a long period of time (I suggest 2 days for their body to recover). Sound great, you sacrifice your follower and absorb the full potential of their Health and Magika. (Since this is killing them it should be significantly better than simple feeding) Maybe fully recover magika, health, and stamina and you also gain a healthy heart for use later I think if you are in combat the chance for a healthy heart should be lower. Maybe say 25%. But you should not be considered in combat once the last bad guy dies. I also think the timing should be 15-30 seconds. 10 seconds to harvest a heart is very limited.