Two more wizard mode methods from me to kill individuals peacefully (and at your own risk):
1. Clone yourself.
2. Equip your clone with a thunder hammer.
3. Piss him off.
4. Stand between the clone and the individual you want to kill and let your clone attack.
Of course, you may want some good armour and electricity resistance and a lot of healing. Petrus can't be killed this way, but it works pretty well on Hulbo or Richel Decos (then again, there are easier ways).
The second method is simpler:
1. Get a pet kamikaze dwarf.
2. Give him a backpack.
3. Piss him off at a distance and make him explode near somebody friendly.
Try doing that in the cathedral gunpowder room... of course, you won't survive that, and it probably won't deal too much damage, but it's still funny.
Not as cool and easy as my Enner Beast method but it also works
Finally, I also tried, in CVS, equipping a clone with an activated Holy Hand Grenade, but unfortunately no matter who's holding it you're still considered the one who pulled the pin and get killed for it.