Vahki The Vahki are robotic order enforcement squads from the fictional LEGO BIONICLE storyline ; mainly the first half of the " BIONICLE Adventures " story arc . Overview . The Vahki were designed by Nuparu to help keep the peace in Metru Nui , and were produced en masse by the city ' s Po - Matoran . With the ability to transform from a biped to a quadruped state , the Vahki were programmed with one directive : to stop lawbreakers by any means necessary . Though Vahki often tried to stop the Toa Metru , they were not evil and obeyed any order they were given by Turaga Dume . They did not knock on doors - they smashed them down . One thing that " did " deter them a bit was deep water - even the Bordakh model , which were better adapted for swimming than the other kinds of Vahki . Their speech was normally in inaudible frequencies , which were translated for Dume by special equipment . Each Vahki was also equipped with a built - in Kanoka Disk launcher and some flight ability . When Makuta revealed that he had been posing as Dume for some time , he absorbed the city ' s entire power grid to increase his power quickly . Most of the Vahki that were in their hives were destroyed by the feedback power surge , but the survivors changed . . . Their speech was now at normal speed and frequency , can repair themselves , and their staffs could now destroy anything in their path . Most importantly , their programming was twisted : they decided that order could best be kept in the city if nothing was left alive . However , even this new ruthlessness did not protect them when the Visorak invaded the city ; and all Vahki have been destroyed . At present , the Matoran have no interest in rebuilding the Vahki . However , it is possible that the Dark Hunters or the Brotherhood of Makuta may have gotten their hands on Vahki technology . Vahki Models . Nuurakh patrol the district of Ta - Metru , and prefer to strike with swift ambushes . At times when they can ' t find lawbreakers , they have been known to start fights with each other that other Vahki have to break up . Nuurakh carry Staffs of Command that fill a target ' s mind with one single directive that they will follow until the stun wears off hours later . Bordakh , the Vahki assigned to Ga - Metru , loves to chase offenders and have even been known to let targets go in order to continue the pursuit . The Bordakh ' s Staffs of Loyalty make victims such zealous supporters of order that they will even help the Vahki apprehend their friends . Vorzakh , peace keepers of Le - Metru , won ' t let anything stand between them and a lawbreaker - literally . They will level everything in the path of their pursuit . Their Staffs of Erasing can temporarily eliminate a target ' s higher mental functions , leaving only their motor functions intact ; Le - Matoran have gotten used to seeing these sorts of victims , known as " shamblers " . Zadakh , who are the enforcers of Po - Metru , are fearless to the point of recklessness and are always eager to jump into a fight . Their Staffs of Suggestion leave victims willing to follow orders from just about anyone for several hours . Rorzakh patrol Onu - Metru and are relentless in their pursuit , continuing even if it means their own destruction . Their Staffs of Presence allow them to see and hear everything that their target does , often without the target even being aware that the Vahki are eavesdropping . Keerakh , as befits the future - focused district of Ko - Metru , have an uncanny ability to deduce a target ' s destination and then get there first . Toa Nuju used this to his own advantage in searching for the Ko - Metru Great Kanoka Disk : in trying to beat Nuju to the Disk , the Keerakh led him directly to its location . They carry Staffs of Confusion that distort a target ' s sense of time and place . Specialized Vahki . When regular Vahki cannot contain a disturbance ; a bigger , specialized machine may be called in ( though the Kralhi is a retired model ) : Kraahu . Unlike the Vahki , who have a central mechanism governing their intelligence , the Kraahu ' s knowledge centers are located throughout its body . The advantage of this is that the Kraahu can actually split apart and send its individual pieces to act independently . This allows it to challenge multiple foes by sending its six legs off in six different directions , while its other compoments monitor the area and defend against attacks . As a single unit , the Kraahu is capable of sending out clouds of stun gas . This gas is also used in the Onu - Metru Archives to put Rahi in stasis . Kraahu parts also give off a powerful electrical shock when touched . Kranua . An extremely specialized Vahki model , the Kranua is called into action less than even the Kraahu . Powerful and bulky , the Kranua is capable of changing into living sand , sliding through cracks or gratings , and changing back . When the Toa Metru were searching for a way back to Metru Nui , they encountered the Kranua and Vakama managed to turn it to solid glass . Matau made the finishing touch by toppling it over and smashed to pieces . Krahli . The Krahli were the prototypes of the law enforcers . They were scorpion - like machines that would absorb energy from law breakers to tire them out . Because of this method , workers became too tired to work from the Krahli ' s effect , leading them to be replaced by the Vahki and driven out of the city . The majority of them have been destroyed in a large battle in the underground river leading to Mata Nui . It is uncertain as to how many remain . Many of the Kralhi joined with an underground - dwelling Matoran named Mavrah who studied water Rahi against Turaga Dume ' s will . The Toa Metru caught up with him , followed by Vahki , and a four - way battle between Kralhi and Rahi , Vahki , and Toa began . Mavrah soon saw the error of his ways , but water caused him to drown .