Ethereal

Ghosts are insubstantial creatures whose bodies are ethereal. They can move through solid objects and therefore suffer no penalties for moving over difficult terrain or obstacles. They can move through buildings just as easily, but they cannot move through living creatures.

Fear

Ghosts are supernatural creatures which cause fear as described in the Warhammer rulebook.

Combat

Ghosts cannot be harmed in combat except by attacks from magic weapons or daemons. They are also affected by magic spells. They can still be beaten in hand-to-hand fighting because combat results are not wholly dependent upon casualties.

Immune to Psychology

Ghosts are not affected by psychology themselves. They are immune to fear, terror, panic and all other psychology tests.

Combat Results

If they are beaten in combat, fail their break test and are forced to flee then Ghosts are immediately destroyed. If they win the combat then their defeated enemy may flee automatically (as troops defeated by creatures which cause fear are automatically broken if outnumbered).

Otherwise, a unit fighting Ghosts must take a break test at the end of every turn of hand-to-hand combat, and will flee if this is failed. This means it is possible for a unit to win the combat, but still end up fleeing if the Ghosts are not destroyed.