Helpless
From Legends of Cphera
A helpless character is Paralyzed, bound, sleeping, Unconscious, or otherwise completely at an opponent’s mercy. A helpless target is treated as having an Agility of 0. Conversely, conditions that reduce an Agility (or Strength) score to 0 usually make the character helpless. Melee attacks against a helpless target get a +4 bonus.
An enemy can use a melee weapon to deliver a Coup de Grace to a helpless foe.