when does THIS ever happen the game?!
Someone apparently resurrected the skeleton summoner (from under the warriors' guild), cast Aura of Command on it, and brought it with them to the wastelands. It starts summoning skeletons when any enemy are within range, which can add up (as shown in the screenshot), though they do not follow you.
The skeleton summoner is one of the creatures you can resurrect and cast Aura of Command on which will not collapse when you sleep.
