Resurrected creatures will also turn hostile if you run away a bit and return, though teleporting is usually faster (if your home base / other teleporter is in the same map area).
There are several level bonuses in the game, and a couple times I used this technique to make sure I went up a level before getting the level bonus (to maximize the experience points received).
In general, it works best if you use this on a fair sized group of opponents (perhaps lizards in the Verdistis sewers or Dark Forest, which have a small chance of dropping a gold charm when killed), or a strong opponent that always drops something when defeated (though gold / loot is easy enough to come by later in the game). I has this skill maxed from purchased spell books before I got around to trying it out (in Iona's dungeon, with one of the guardians beside the three pyramids and the teleporter pad).
There was a post in the old forum about resurrected monsters that did not die when your character slept, which might come in handy for a necro character. That person brought such creatures to his home base, and either Banished them or cast Aura of Command on something else (don't recall) to leave them there.
The skeleton summoner from under the warrior's guild was one example, though it is very over-powered. It starts summoning at the sight of hostile creatures, and the resulting skeleton army can quickly overwhelm the opposition.
IIRC the dragon rider that Zandalor kills and Shrimpo also do not die when your character sleeps.
Are you in the Verdistis sewers, or Ars Magicana? If you are in Verdistis, Finnigan in the Ducal inn cellar has a quest for you. From you agility, it doesn't appear you have done this quest yet...
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