Alter Aeon Online Help

Keywords are:  'ethereal ghosts'

Ethereal means intangible or insubstantial, the opposite of material. Ethereal
creatures are generally bodiless entities that are purely spiritual, such as
some kinds of faeries, demons, angels or elementals. There are also entities
such as ghosts, spectres, wraiths and shades, which are disembodied spirits.
Some varieties of disembodied ethereals are undead in nature, others are of a
less defined sort, taking energy from shadow or elemental sources rather than
spiritual ones. Ethereal creatures are not alive, and one generally cannot
obtain meat, blood, skin, bones or other parts of from them, even if they
leave behind a corpse. Some may leave behind residue, such as ectoplasm.

Ethereal creatures cannot be harmed by normal weapons or attacks. They only
take only half damage from fire, ice, electrical and breath damage. Weapons
with the magic or nonorm damage types can deal full damage to them.

Most spells harm ethereal entities, saves ones that are largely physical
in nature such as crystal spear or fist of the earth. A few, such as
the necromancer spell spectral claws, are more damaging to ethereal
creatures than living ones.