Keras Crab
Coral Crab Rahi of Ga-Wahi and the Pit
A large coral crab Rahi native to the ocean of Ga-Metru and the reefs of Ga-Wahi, briefly tamed by the Ga-Koro Defense Force during the Bohrok War and later mutated into the standing infantry of the Barraki Carapar in the airweed fields of Mahri Nui.
The KerasKerasLarge coral crab Rahi native to the ocean of Ga-Metru and the reefs of Ga-Wahi, briefly tamed during the Bohrok War and later conscripted by Carapar. Crab was a coral crab RahiRahiThe Rahi were the biomechanical wildlife of the Matoran Universe, built largely by the Brotherhood of Makuta, ranging from background fauna to engineered war beasts. of the Matoran UniverseMatoran UniverseA civilization of biomechanical beings living inside a colossal robot, destroyed when Teridax seized control., found in the Silver Sea off Ga-MetruGa-MetruGa-Metru is a district of Metru Nui, home to the Ga-Matoran and the Bordakh. and later in the reefs of Ga-WahiGa-WahiGa-Wahi was a region situated to the east on the island of Mata Nui, inhabited by Ga-Matoran and various Rahi. The region once fell under the domain of Teridax, though that connection did not endure. Ga-Wahi no longer existed in later records.. The species was reclusive and territorial, famous for protecting its undersea home with great ferocity. The one recorded time it worked with the Matoran came during the Bohrok WarBohrok WarThe 2002 swarm that nearly destroyed Mata Nui when Teridax triggered the Bohrok's awakening ahead of schedule., when a few displaced KerasKerasLarge coral crab Rahi native to the ocean of Ga-Metru and the reefs of Ga-Wahi, briefly tamed during the Bohrok War and later conscripted by Carapar. were tamed by the villagers of Ga-KoroGa-KoroGa-Koro is a village on the island of Mata Nui, inhabited by the Ga-Matoran and associated with both Nokama and Gali. The settlement was formerly under the power of Teridax. and used as armoured mounts against the BohrokBohrokHive-minded mechanical creatures designed to reshape worlds, the Bohrok represent a threat the Toa Mata never expected.. Much later, a mutated population served in the army of the BarrakiThe BarrakiSix warlords who built an empire spanning most of the Matoran Universe, fell to a Brotherhood strike, and spent millennia imprisoned in the Pit. CaraparCaraparOne of six Barraki warlords imprisoned for 80,000 years, Carapar sought the Mask of Life and became expendable muscle for a final, fatal mission. in the waters around Mahri NuiMahri NuiA matoran settlement that sank, survived, and was ultimately crushed beneath Voya Nui, leaving behind one of Bionicle's most poignant lost civilizations.. (BIONICLE: Encyclopedia Updated; Inspired by BIONICLE: Keras; BIONICLE Legends 6: City of the Lost)
Habitat and disposition#
In the time of Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive., the KerasKerasLarge coral crab Rahi native to the ocean of Ga-Metru and the reefs of Ga-Wahi, briefly tamed during the Bohrok War and later conscripted by Carapar. lived in the Silver Sea off Ga-MetruGa-MetruGa-Metru is a district of Metru Nui, home to the Ga-Matoran and the Bordakh., the water district of the city. After the Great CataclysmThe Great CataclysmThe day Makuta Teridax put the Great Spirit to sleep, the Great Spirit Robot fell from the sky, Metru Nui flooded, and Voya Nui tore loose from the Southern Continent., several came to occupy the reefs of Ga-WahiGa-WahiGa-Wahi was a region situated to the east on the island of Mata Nui, inhabited by Ga-Matoran and various Rahi. The region once fell under the domain of Teridax, though that connection did not endure. Ga-Wahi no longer existed in later records. on the island of Mata NuiMata Nui (Location)An island created by accident on the Great Spirit's face, home to the Matoran for a thousand years., in the waters around Ga-KoroGa-KoroGa-Koro is a village on the island of Mata Nui, inhabited by the Ga-Matoran and associated with both Nokama and Gali. The settlement was formerly under the power of Teridax.. (BIONICLE: Encyclopedia Updated)
The species' temperament shaped every recorded meeting with it. KerasKerasLarge coral crab Rahi native to the ocean of Ga-Metru and the reefs of Ga-Wahi, briefly tamed during the Bohrok War and later conscripted by Carapar. were highly reclusive, territorial, and famous for the ferocity with which they defended their reef homes. They were sensitive to strong sunlight and lived on fish. (BIONICLE: Rahi Beasts; Inspired by BIONICLE: Keras)
The Bohrok War mounted-crab program#
The one recorded time the KerasKerasLarge coral crab Rahi native to the ocean of Ga-Metru and the reefs of Ga-Wahi, briefly tamed during the Bohrok War and later conscripted by Carapar. crossed from hostile wildlife to ally came during the Bohrok WarBohrok WarThe 2002 swarm that nearly destroyed Mata Nui when Teridax triggered the Bohrok's awakening ahead of schedule.. The GahlokGahlokWater-element Bohrok swarms that flooded Mata Nui's aquatic zones with relentless purpose., the water BohrokBohrokHive-minded mechanical creatures designed to reshape worlds, the Bohrok represent a threat the Toa Mata never expected. swarm, drove a number of KerasKerasLarge coral crab Rahi native to the ocean of Ga-Metru and the reefs of Ga-Wahi, briefly tamed during the Bohrok War and later conscripted by Carapar. out of their home waters and onto the beaches of Mata Nui. (Inspired by BIONICLE: Keras)
Volunteers from the Onu-MatoranOnu-MatoranEarth-wielding Matoran of the deep who adapted to darkness and built the Matoran Universe's defensive cavalry. UssalryUssalryOnu-Koro's branch of the Mata Nui Military, made up of Onu-Matoran riders mounted on tamed Ussal crabs and led by High Commander Onepu. helped the villagers of Ga-KoroGa-KoroGa-Koro is a village on the island of Mata Nui, inhabited by the Ga-Matoran and associated with both Nokama and Gali. The settlement was formerly under the power of Teridax. tame a few of the displaced crabs as partners against the swarms. The Ussalry already rode UssalUssalSix-legged crustacean Rahi domesticated across Metru Nui and Mata Nui for cargo, mining, and sport. Backbone of Matoran labor. crabs as cavalry on Mata NuiMata Nui (Location)An island created by accident on the Great Spirit's face, home to the Matoran for a thousand years., which goes some way to explaining why they were the ones to volunteer. (Inspired by BIONICLE: Keras)
The tamed KerasKerasLarge coral crab Rahi native to the ocean of Ga-Metru and the reefs of Ga-Wahi, briefly tamed during the Bohrok War and later conscripted by Carapar. were fitted with special riding plates and could carry their riders across both sea and land. In return for shelter from the sun and a meal of fresh fish, these fierce and clever crabs were content to serve as defenders of the village. (Inspired by BIONICLE: Keras)
After the war#
The story doesn't follow the Ga-Koro KerasKerasLarge coral crab Rahi native to the ocean of Ga-Metru and the reefs of Ga-Wahi, briefly tamed during the Bohrok War and later conscripted by Carapar. past the Bohrok swarms. Shelter and fish in exchange for service is the last word the sources give on the arrangement, and the crabs play no part in the later Toa NuvaToa Mata and Toa NuvaSix biomechanical heroes created by the Great Beings to awaken Mata Nui and defeat the Brotherhood, transformed once and tested across an entire age. stories on Mata Nui. (Inspired by BIONICLE: Keras)
Carapar's army in the Pit#
The species returned in a very different setting. The BarrakiThe BarrakiSix warlords who built an empire spanning most of the Matoran Universe, fell to a Brotherhood strike, and spent millennia imprisoned in the Pit. CaraparCaraparOne of six Barraki warlords imprisoned for 80,000 years, Carapar sought the Mask of Life and became expendable muscle for a final, fatal mission., one of the warlords imprisoned in the PitThe PitThe Order of Mata Nui's maximum-security underwater prison where the Barraki warlords were held until catastrophe broke their chains., had a large number of Keras in his undersea army, along with the Pit War Tortoises he had recruited. (BIONICLE: Encyclopedia Updated; BIONICLE Legends 6: City of the Lost)
The mutagenMutagenPit Mutagen was a power-source energy that leaked into the waters of The Pit during the Great Cataclysm and mutated almost every being exposed to it. in the waters of the Pit, the same substance that had changed the BarrakiThe BarrakiSix warlords who built an empire spanning most of the Matoran Universe, fell to a Brotherhood strike, and spent millennia imprisoned in the Pit. themselves, had made these Keras vicious. When the Kanohi IgnikaThe Mask of Life (Kanohi Ignika), explainedA failsafe forged by the Great Beings to recharge a god. It curses everyone who touches it, and by the end of Bionicle it had learned how to be a hero. enlarged a venom eel to enormous size, the eel ate several hundred of them. (BIONICLE Legends 6: City of the Lost)
The Air Fields engagement#
The best-known meeting between CaraparCaraparOne of six Barraki warlords imprisoned for 80,000 years, Carapar sought the Mask of Life and became expendable muscle for a final, fatal mission.'s Keras and the Toa MahriToa Inika and Toa MahriSix ordinary Matoran transformed by lightning from the Red Star into heroes who ultimately revived the Great Spirit itself. came during the hunt for the KanohiKanohiMasks that grant powers and sustain life, they're the most vital artifact in the Matoran Universe. Ignika, the Mask of LifeThe Mask of Life (Kanohi Ignika), explainedA failsafe forged by the Great Beings to recharge a god. It curses everyone who touches it, and by the end of Bionicle it had learned how to be a hero.. Keras crabs had taken over the fields of air, the airweed fields that supplied Mahri NuiMahri NuiA matoran settlement that sank, survived, and was ultimately crushed beneath Voya Nui, leaving behind one of Bionicle's most poignant lost civilizations. with air, and the Matoran of the city sent the newly arrived Toa to force them out. (BIONICLE Legends 7: Prisoners of the Pit)
No fight followed. The crabs retreated of their own accord when the Barraki came to negotiate with the Toa. (BIONICLE Legends 7: Prisoners of the Pit)
Place in the bestiary#
The Keras has an unusual spread among the catalogued RahiRahiThe Rahi were the biomechanical wildlife of the Matoran Universe, built largely by the Brotherhood of Makuta, ranging from background fauna to engineered war beasts. of the Matoran UniverseMatoran UniverseA civilization of biomechanical beings living inside a colossal robot, destroyed when Teridax seized control., turning up in the Silver Sea of Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive., the reefs of Mata Nui and the deep waters around Mahri NuiMahri NuiA matoran settlement that sank, survived, and was ultimately crushed beneath Voya Nui, leaving behind one of Bionicle's most poignant lost civilizations.. (BIONICLE: Encyclopedia Updated; BIONICLE Legends 6: City of the Lost)
It was also recruited by both sides at different points, first as a partner of Ga-Koro against the Bohrok and later as a soldier in a Barraki army. Its hostility was the rule, and those two periods of service, one tamed and one mutated, were the exceptions. (Inspired by BIONICLE: Keras; BIONICLE Legends 7: Prisoners of the Pit)
Frequently asked questions
- What is the Keras Crab?
- The Keras Crab was a coral crab Rahi of the Matoran Universe, found in the Silver Sea off Ga-Metru and later in the reefs of Ga-Wahi. It was reclusive and territorial, and famous for defending its undersea home with great ferocity.
- How were Keras Crabs tamed during the Bohrok War?
- When the Gahlok swarm drove a number of Keras onto the beaches of Mata Nui, volunteers from the Onu-Matoran Ussalry helped the villagers of Ga-Koro tame a few of the displaced crabs as partners against the Bohrok.
- How were the tamed Keras used in battle?
- The tamed Keras were fitted with special riding plates and could carry riders across both sea and land. In return for shelter from the sun and fresh fish, they were content to serve as defenders of Ga-Koro.
- What happened to the Keras in the Pit?
- The Barraki Carapar kept a large number of Keras in his army, made vicious by the Pit mutagen. A venom eel enlarged by the Kanohi Ignika ate several hundred of them.
- Why did Carapar's Keras army not fight the Toa Mahri?
- The Matoran of Mahri Nui sent the Toa Mahri to drive the Keras out of the fields of air. The crabs retreated on their own when the Barraki arrived to negotiate with the Toa, so no fight took place.
Sources
- BookBIONICLE: Rahi Beasts, Greg Farshtey and Jeff James, Scholastic, 2005
- BookBIONICLE: Encyclopedia Updated, Greg Farshtey, Scholastic, 2007 (Keras and Carapar entries)
- BookInspired by BIONICLE: Keras, LEGO Club.com building instructions with creature profile, The LEGO Group
- BookBIONICLE Legends 6: City of the Lost, Greg Farshtey, Scholastic, 2007
- BookBIONICLE Legends 7: Prisoners of the Pit, Greg Farshtey, Scholastic, 2007
Spotted a factual error or a primary source we missed? Email a correction. Every flagged claim gets reviewed.
Followed from this entry

Keras
Large coral crab Rahi native to the ocean of Ga-Metru and the reefs of Ga-Wahi, briefly tamed during the Bohrok War and later conscripted by Carapar.
Mutagen
Pit Mutagen was a power-source energy that leaked into the waters of The Pit during the Great Cataclysm and mutated almost every being exposed to it.

The Barraki
Six warlords who built an empire spanning most of the Matoran Universe, fell to a Brotherhood strike, and spent millennia imprisoned in the Pit.

Rahi
The Rahi were the biomechanical wildlife of the Matoran Universe, built largely by the Brotherhood of Makuta, ranging from background fauna to engineered war beasts.

Ussal
Six-legged crustacean Rahi domesticated across Metru Nui and Mata Nui for cargo, mining, and sport. Backbone of Matoran labor.

The Pit
The Order of Mata Nui's maximum-security underwater prison where the Barraki warlords were held until catastrophe broke their chains.
Mentioned in2 entries
The Toa Mahri Descent into the Pit
The transformation that ended the Toa Inika, the Barraki's war on the newcomers, and the moment Matoro learned that his Maxilos escort was Teridax.
Toa Mahri: The Toa Who Saved the Universe
The Toa Mahri were the water breathing form of the sixth Toa team, transformed by the Mask of Life on the way down to the drowned city of Mahri Nui. They fought the Barraki for the mask and recovered it at the cost of one of their own.
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