Kill stuff without making anyone hostile to you exploit

If you want to defeat something without making people hostile, summon something and let your summonings take care of the rest.

I have used this sucessfully to clean out many quest-releated targets without making the rest of the area hostile, such as the shaman at the Trelis excavation, the Shaman in Silden etc, the trick is just to get your summoning to attack the right target and then manage to get rid of the summoning before it kills any other named/vital NPC.

Yep, as explained in the Beliars Shrine thread I think it is. You can also use monsters you pull from the wild, such as trolls.