Darthmus has unleashed his dark side as he has unlocked his full shadow abilities. Upgrading the way he did, His mask changed into a more devious evil mask that has the power of teleportation through dark matter. His new mask has unknown power that if completely 100% complete would destroy voya nui. Considering this he has been able to keep his dark-side under control. Seeing the goodness inside of him dextrix ninja master took him in and trained him to defend his self from rahi without killing them and villains without eating them :).