Rahi Rahi are animals in BIONICLE . Most Rahi live in the wild . The word " Rahi " is from the Matoran language , and roughly translates to " not us " or " wildlife " . Most Rahi vehicles and characters listed were created by the Brotherhood of Makuta , whose original job was to create and alter creatures as needed . The Keetongu and the Manas may be exceptions to this . Some definite exceptions are a number of giant sea beasts that were the first Rahi created and predate even the Brotherhood . The beings most knowledgeable about the ways of Rahi are the Rahaga , former Toa heroes who have become experts in tracking and capturing the beasts ; they now use their skills for the creatures ' protection . While living in the city of Metru Nui , they have written extensive records of many Rahi species that appeared there ( the " BIONICLE : Rahi Beasts " guide ) . As a general rule , all non - intelligent creature seen in BIONICLE are considered a Rahi , and those that have such intelligence are not . However , there are exceptions to both these rules : a few beings ( like Krahka , Tahtorak , Keetongu , and the Artakha Bulls ) have humanlike intelligence and are still considered Rahi . At the same time , some lesser - intelligence beings do not seem to be considered Rahi : mindless Bohrok and Rahkshi , and the organic Krana and Kraata that control them , are not included in the Rahaga ' s records . Featured Rahi . While most Rahi are little more than generic animals , a few have appeared in prominent roles in the storyline , either for the special threat they present to the Toa or for their unique intelligence and personality , being full - fledged characters themselves . Fenrakk . Fenrakk are a species of spiders with acidic saliva . They are native to the island of Voya Nui . The most well - known Fenrakk was enlarged by the Mask of Life and forcibly fused to Vezon , as a way of cursing Vezon . The Mask of Life also gave Vezon the ability to absorb kinetic energy , and he shared this power with Fenrakk , allowing them to grow stronger with every physical attack made by them or against them . This ability makes the two unaffected by all physical blows ( as they immediately grow strong enough to withstand the attack ) , and the mask also grants them protection from other dangers such as lava . The Toa Inika have tamed smaller , normal - sized " Fenrakk Spawn " to use as mounts in their sieges against the Piraka ' s stronghold . Kardas . When Vezon and Fenrakk were defeated by the Toa Inika and the duo plunged into lava of their own free will , the Mask of Life evolved Fenrakk further into a new dragon - like creature that Vezon called Kardas . Kardas naturally generates concussive force inside its body that it can fire out its mouth ; in fact if it " doesn ' t " release this force periodically , the concussive force will cause it to explode . It does not appear to have Fenrakk ' s ability to absorb kinetic energy . Vezon mentioned that if he were to plunge into the lava with Kardas , an even more terrifying ' steed ' would emerge with him . After the Toa took the Mask of Life , Vezon and Kardas were no longer fused , and thus went their separate ways . Kardas traveled to the surface , and has since lost a fight against a Tahtorak that was on Voya Nui . Flying north , it arrived on the island of Mata Nui and was injured in a conflict with the Bohrok . Toa Gali helped to heal its injuries , but what it will do next is anyone ' s guess . Keetongu . Keetongu is the name of one of a race of intelligent Rahi , and is the only one of his species has been seen , and might be the last of his kind after his island was conquered by the Visorak . Although his name is pronounced as it is , Onewa thought it was " The Key to Nongu " . Keetongu lived in a Ko - Metru cave that could be accessed by an underground chute in Metru Nui . The Toa Hordika and the Rahaga found him and got him to help defeat the Visorak and reverse their mutations . In the Toa ' s siege of the Coliseum , Roodaka baited Keetongu into killing the Visorak ' s king , Sidorak . When Makuta later came to the city , Keetongu sensed his evil and attacked , only to be beaten into unconsciousness . He now comes and goes from the city as the Rahaga do , but was not present to welcome the Matoran upon their return . Keetongu can heal anyone afflicted by poison or venom , as long as the poison has not fully taken effect ; and his spinning shield array can absorb attacks that he can then send back at his opponent using his Rhotuka spinner ( though he cannot absorb the spinners of Roodaka or Sidorak ) . His single visible eye cannot actually see , but it can detect the good or evil in someone ; the eyes that he sees with are hidden behind it . Rahaga Norik even stated that " Keetongu sees with one eye what we have missed with all of ours . " He also carries a climbing claw that can be used as a melee weapon . He possesses great strength , rivaling that of a Makuta . As Keetongu is the only one of his race left in existence , it is impossible to tell which powers are shared by the entire race . He speaks in a grinding language intelligible only to himself and the Rahaga . Krahka . Krahka is an intelligent shapeshifting Rahi who can imitate any form she has seen and can also gain knowledge of those she copies . She can mix and match pieces of different forms , but only with effort . Krahka was first encountered in Metru Nui defending her territory in the Archive ' s Maintenance Tunnels from the Toa Metru . She later joined the Toa Hordika in fighting the Visorak ; in a battle in Le - Metru she disappeared with Tahtorak and Zivon into the Zone of Darkness when a nearby Kahgarak ' s Rhotuka struck the trio . She and Tahtorak were able to escape to Voya Nui a thousand years later , when Brutaka opened a portal there intending to trap his ex - partner Axonn . She then adopted the form of a flying Rahi and then began flying over the Endless Ocean . It seems she is headed for the island of Mata Nui so she can make her way back down to Metru Nui . Krahka is best known for a multi - armed form that combines aspects of the six Toa Metru . According to Rahaga Pouks , the rest of her kind were wiped out by the Visorak . Pewku . Pewku is an Ussal crab ( see below ) that has been a favorite pet of several Matoran . On Metru Nui , she pulled carts for her owner , Orkahm , and after the Great Cataclysm Toa Whenua took a liking to her and suggested they bring her to Mata Nui . Sometime over the next thousand years , she passed into the care of Onepu , who rode her in the Great Ussal Races . Eventually , she was retired from racing , instead giving " taxi crab " rides between Po - Koro and Onu - Koro . It was on this job that Takua met her , and he later on adopted her ; She would later be Takua ' s and Jaller ' s steed and traveling companion in their search for the Toa of Light . When Takua became Toa Takanuva , he gave Pewku to Jaller . Now that Jaller has become a Toa himself , it is unknown who will take custody of Pewku , but she has befriended Kapura . Pewku ' s name used to be spelled " Puku " , and was changed by Takua shortly after the Bohrok invasion . A little while later , just before the search for the Toa of Light , Pewku evolved to her current form , larger than most Ussal crabs . Rahi Nui . The Rahi Nui is a mutant Rahi created to serve the Brotherhood of Makuta as a tracking beast for Nidhiki and Krekka , though it was lent to the Dark Hunters for a time . It was specifically bred to hunt Toa and feed on their elemental energy , and it has the head of a Kane - Ra , the forelegs of a Tarakava , the body and hindlegs of a Muaka , the stinger of a Nui - Jaga , and the wings of a Nui - Rama . With the ability to use the aspects of these Rahi to their full capacity , it also had the eight basic Kanoka Disk powers , but lost them in its battle with the Toa Metru , where they made it grow so big its atoms drifted apart ( though the creature was able to pull itself back together eventually ) . It was more recently defeated again when it got its horns stuck in a wall while fighting the Toa Nuva . Toa Lesovikk has also had an encounter with the beast in the past . Tahtorak . Tahtorak are massive 40 foot dragon Rahi that can speak the Matoran language ; they have been seen on several islands including Zakaz and Keetongu ' s homeland . ( See under " List of Rahi " below for information on the species in general . ) One Tahtorak specifically has been seen in Metru Nui , and it constantly demands " Give me the answer ! " , without asking his question ( which is actually " Where am I ? " or " How did I get here ? " ) . It has since been revealed that it was Brutaka who dropped it into the center of Metru Nui just for fun . " This Tahtorak was last seen disappearing into the Zone of Darkness with Krahka and Zivon . Ironically , Brutaka was responsible for Tahtorak ' s and Krahka ' s escape from the Zone of Shadow a thousand years later , as he opened a gate to try to trap his former friend Axonn in the Zone . While Krahka was able to fly away from their escape point of Voya Nui , Tahtorak was stranded there . It got into a fight with another of Voya Nui ' s beasts , the Kardas dragon , and won ; afterwards Axonn had his associate Botar teleport it away . Botar selected Xia as its destination , and it has begun to go on a rampage - leading to a fight with yet another beast , the Kanohi Dragon . Visorak . Visorak are highly trained spider - like soldiers , once " employed " by the Brotherhood of Makuta under Sidorak and Roodaka . These armies roamed the world , encasing Rahi and sometimes Matoran in cocoons and spinning webs everywhere . Inside the cocoons , there are sharp barbs that inject the victims with a mutating Hordika venom . The armies are now disbanded and scattered , though some have returned to the Brotherhood ' s control . Behind the Scenes . Name Changes . Following a lawsuit by Māori activists , some Rahi names based on the Māori language were changed : Unrelated to the lawsuit , the " Mukau " was renamed the " Mata Nui Cow " because LEGO ' s story team felt that the pun on " Moo - cow " was too ridiculous . Rahi Building Challenge Credits . The March / April 2004 LEGO Club Magazine presented the Rahi Building Challenge , where entrants could have their creations entered into BIONICLE canon , and the grand prize winner would be drawn into comic issue # 21 . The following are the winning entries , featured in the " BIONICLE : Rahi Beasts " guidebook : References . < div class = " references - small " > General information comes from the " BIONICLE : Rahi Beasts " guidebook ; see List of BIONICLE media .