The Undead are creatures risen from the dead, reanimated and given motion again- although most Undead are never truly themselves as they were before. Some undead are Ethereals; spirits, brought back to life in an immaterial form upon the material world. Others, such as the common Skeleton, are enchanted bodies or bones, and are sorely lacking in spirit and soul- only clinging to memories and faint traces that remain in their ancient bones. What remains of the Undead is a key factor in understanding them, truly.

They are either the result of magical corruption, a late, botched or remiss resurrection, or an intentional magical reanimation, such as necromancy.