The Kanohi Felnas was the Mask of Disruption, worn by Makuta Gorast. It could make the powers of others run wild.1
Notes
Gorast's Kanohi Felnas, the Mask of Disruption, let her make a Toa's powers go wild.2
A power needed to be active for the Felnas to disrupt it.3
It was not one-of-a-kind.4