The Kanohi Fexan is the Mask of Fear, one of the few Legendary Kanohi. It has the power to create fear into anyone's mind, stunning them into submission. It also has the power to make one's worst nightmares become reality. The mask also has the power to transform itself, making it impossible to tell one Kanohi from another. The mask also has one other power: The ability to send one to the Nightmare Realm, a reality that only exists through the Fexan. With a Kanohi Fexan activated, it makes the effects of the Nightmare Realm more powerful.