The Terror Bark is a Hardmode summon weapon dropped from Waking Nightmares. It summons a Terror Fiend minion and a Nightmare Eye on top of player's head. The Terror Fiend will attack enemies. After attacking an enemy the Terror Fiend has a chance to shoot wither bolts that home in on enemies and may cause them to erupt into Nightmare Explosions. Additionally, minions will receive a buff which increases their damage and knockback when the Nightmare Eye is active. When there are no enemies around, the Terror Fiend floats around the player.
Its best Modifier is Ruthless or Mythical; Ruthless provides a smaller array of stat bonuses but is stronger on what it has, and Mythical has a wider array of stat bonuses, but are weaker than the latter.