From DDO wiki
- Purple named bosses are immune to this effect.
- Red named bosses can take only up to 10 points of strength damage and can never be rendered helpless.
- The effect only occurs if the attack hits and deals at least 1 point of physical damage after the target's Damage Reduction is applied. (Sneak attack damage adds to an attack's physical damage, as do enhancement bonuses, Strength bonuses, and critical hits.)
- A creature reduced to 0 strength becomes helpless.
Unique name loot with this effect: