Causes Fear

Causes Fear is an attribute which makes the hero, lord or unit frighten all nearby enemy units, reducing their leadership, and making itself immune to fear. Fear penalties do not stack so, for example, multiple units with Causes Fear attacking a hero will debuff its leadership only once. The malus is the same regardless of whether it is a hero, lord or unit that has the attribute.

(needs tiding up)

Fear

 * Units with the Can Cause Fear or Causes Fear attribute, slightly reduce the leadership of nearby enemy units (-8 Leadership in a 30m radius).
 * Most Monstrous infantry units cause fear.
 * All Vampire Counts, Vampire Coast, and Tomb Kings units cause fear.
 * Units which cause fear are immune to fear effects.

Lore
"This unit frightens all enemy units, reducing their leadership when nearby. It is also immune to fear. Fear penalties do not stack."