The Twin-Bladed Black Fire Sword was the standard weapon used by all Maxilos robots, the Order of Mata Nui's guards of The Pit. It could also be used to channel the internal energies of the robots. The Maxilos possessed by Makuta Teridax during his time in Mahri Nui and the Pit carried one of these swords. While possessing the robot, Teridax could channel his own shadow energy through the sword, in addition to the robot's own internal energy.