The Viroids are a mysterious third faction from the Gorge who appeared after the Codebrick from the Watch Tower was retrieved. They seem to take advantageous abilites and adaptations based on their enemies.
Attack on the Golden CityEdit
The Viroids apparently attacked the Golden City during the time it was first inhabitated, using footsoldiers before they copied the concept of the Battle Machines to build their own. They were defeated and retreated back to the bottom of the mountain, plotting their return.
Return to the MountainEdit
The Viroids then returned years later in their Battle Machines, destroying anything in their way while ascending the mountain. This quickly got the humans and Robots begin to hunt for Code Bricks in order to stop them and their enemies. Their leader Yami soon joined the fight, using the Blazing Phoniex to fight Hitomi until she mysteriously retreated when she saw Hitomi's face.
Yami soon flew the Blazing Phoniex into the Golden City only to surrender to the Exo-Force and reveal herself to be a human. After this little revalation, Keiken personally interrogated her and put her under the begrudging Hitomi's guard after revealing her to be Hitomi's mother. After the defection of their leader, The Viroids returned to the bottom of the mountain to plot their revenge...