Mask of Undeath

The Mask of Undeath was a Kanohi that siphoned off a tiny part of its user's life-force from their body, which it then used to reanimate their body after they died. When killed, the dead body was then animated by the collected life-force and continued its previous objective from life. The mask gave the user no other power and actually slowed down their thinking and movement. While undead, the user lost all illumination in their eyes.

Powerless

 * An unnamed "fixed" Matoran in Karzahni

Trivia

 * The mask was originally part of a BZPower fan project, but BIONICLE writer Greg Farshtey approved it as official.
 * This mask power was inspired by its black eyes and 'deathly appearance'.