Nightmarish is a monster trait that is unique to Diablo III and was first introduced in Beta Patch 14.
Nightmarish monsters have a chance to fear the player on hit and can be triggered from both melee and ranged attacks. The "Feared" debuff lasts for 3 seconds during which the player runs uncontrollably away from the monster. A skull icon appears above the player's head indicating the applied debuff.
This trait can occur for any monster.
Monsters can also be affected by the nightmarish ability if they take friendly fire, such as is the case with an exploding Grotesque.
|Diablo III Monster Traits|
|Diablo III||Arcane Enchanted • Avenger • Desecrator • Electrified • Extra Health • Fast • Fire Chains • Frozen • Health Link • Horde • Illusionist • Invulnerable Minions • Jailer • Knockback • Missile Dampening • Molten • Mortar • Nightmarish • Plagued • Shielding • Teleporter • Vampiric • Vortex • Waller|