Presumably the poor adventurers that previously entered the mine...
Generally low hitpoints and attack, though low AC characters should avoid direct contact due to the random nature of skeletons. The more stuff they are wearing, the more dangerous they typically are. Good source of +2 ATK weapons and +2 AC helms, though more often cursed than not.
Stealth characters should be aware that skeletons detection range in dark dungeons is exceptionally low. If you stay in the shadows and have no light source you can level your stealth very easily by following them and can assassinate them by waiting for the right time to power attack them when they are alone.
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