Skeleton¶

All skeletons are magically animated undead monsters, created as guardians or warriors by powerful evil wizards and priests.

Skeletons appear to have no ligaments or musculature which would allow movement. Instead, the bones are “magically joined” together during the casting of an Animate Dead spell. Skeletons have no eyes or internal organs.

   Be wary of all undead beasts. Aside from the ghouls, ghasts, and skeletons listed
   here, there are animated corpses, warrior skeletons, and even revived wolves
   known as dread wolves. Some of the most powerful undead along the Sword
   Coast, such as the vampiric wolves, are not even affected by normal weaponry
   and require magics in order to kill!
                                                                        —Elminster

Source: bgee/original_manuals/baldurs_gate_1_ee_sword_coast_survival_guide.pdf — "Some Monsters of the Sword Coast" → "Skeleton".